Okay, so I decided I would choose which game from each series that I liked the most, some I haven't played but nonetheless, here's my rankings:
Backyard Baseball: It's classic, but the problem I personally have with it is that it's average mechanics (it's not hard to hit a homerun with just an average linedrive and a screaming linedrive practically gurantees a homerun). I do like that it was unique and wasn't mustered by pros yet, but...
Backyard Baseball 2001:I give this one the best Backyard Baseball game. It improved on the missing mechanics, the AI is a lot smarter, and the characters have depth to them. This game also really spiked up the popularity in the series, as it was my first ever Backyard Sports game I ever got from Staples no less.
Backyard Baseball 2003: I never played this one, but it looks exactly like 2001 with a few new fields. I saw some videos of it, not a fan of the voice work done in this game. Though it did look like you could unlock the championship field which looks neat, but still not enough to warrant me to buy it.
Backyard Baseball 2005: People either love the new 3D or hate it. I'm in the boat that loves the 2005-2006 3D. The things that cost this from being better than 2001 is they cut Vinny the Gooch (WHY??) and replaced him with the less funny Abner Doubleplay who seems like a baseball carbon copy of Chuck Downfield. Another thing is I'm not really a fan of the fields in this game. The only ones I really liked in this one were Steele Stadium and Humongous Memorial Stadium.
Backyard Baseball 2007: YUCK!! Please get this out of my memory...I still remember getting this game and installing and loading and just flat out hating this game. Took away a lot of Backyard favorites (my team was completely disorganized now), Pablo speaks English entirely, no more Sunny Day, Joey MacAdoo, gah! Horrible, stopped buying the series after this until the newest installment.
Sandlot Sluggers: Okay so now we got two new announcers who I wish I could smack in the faces with a line drive and there's no customization...WHAT?? It was always fun mixing the backyard kids up, now there's no customization, you get to choose just one Backyard Sports kid and use their already made up team. The characters do look much better from the 2007 era though, so I guess there's a plus on that. I also do like they added a new storymode which I think if it had been in with the original games they could have been a lot more funner. That and the many new minigames added that I wish could have been in the originals so there are some things this game got right.
Backyard Soccer: Yeah, I'm giving the original the nod on this one. I thought it was the best one because it was all custom teams and no professional teams. I did love playing in the off the wall tournament and the credits to this game was such wonderful music and then there was the epic headlines.
Backyard Soccer MLS Edition: It's alright, but with the addition of pros, now you have to play the professional teams and the pros and it just slides the play in my opinion. I do like they added depth to the characters like what they did in Backyard Baseball 2001.
Backyard Soccer 2004: It's been the longest out of the other sports since soccer got a game. I only played a one hour trial of soccer and Earl Gray's voice just SUCKS in this game. Also, it's 2004 and they have no custom player (none of the soccer's did) but by now, it's inexcusable. I can't remember seeing anything different from this one from MLS Edition but I'll probably order this one soon to give it more of a fair chance.
Backyard Football: I do love this series of games, but the original takes the cake. Some of the small things I like about this game is what takes it. You can create your own plays, the endzones have carpets just like in real football. I just think it's the funnest of all the football ones, but I'll break down in the other ones why they can't have the best football title.
Backyard Football 2002: Something about this game just feels like it's just a generic. Like, nothing goes on. About every line in this game was taken from the original, and I didn't find the fields all that great either. There's also one thing about this game...the players are so damn fast. Like racecar fast, it's so weird.
Backyard Football (Gamecube): I like this more than the 2002 version even though it's basically the same thing. I like it more than the PC because not only are the helmets just like the ones in the NFL but man do they have an awesome championship stadium. I love reaching the Cereal Bowl to play in that stadium and hear the fans, but the passing plays are rather difficult to control in this one, which knocks it off of the best category.
Backyard Football 2004: This game does a lot of things right Backyard Football 2002 couldn't. However, it has a few new downers. Who the heck am I passing too? You can't really tell who anyone is in this game, they all almost look the same and the scoring celebrations are very minimal. You see them on the Score-U-Tronic for like one second and then it goes away. What a shame. Also, their championship is played at a zoo...why? It's not a big stadium like all the others and that's a huge downer. I did like the logo being in center field though.
Backyard Football 2006: Kind of like Backyard Baseball 2005, the things I didn't really find interesting were the fields. I only liked the high school and the championship stadium. But this was the first one where the Backyard kids began to get cut like Kenny, Ronny, and Billie Jean were notably absent in this game. Ronny used to be my safety, so now that he's gone...had to make up a new team. But, it's still a fun game to play, but the passing plays can be pretty hard.
Sandlot Sluggers: The two announcers get even more annoying. I did like the fields better, and the added "Your Backyard" stadium is pretty cool. I also liked Ace Patterson, I think he could have been a cool original Backyard kid and I probably would have chosen him a few times had he been. Sadly, it doesn't look like there will be another sports game he can be in anyway.
Backyard Basketball: I do like it. It does have some pretty cool team names and logos and it's the first original game that gave you your own choice of a home court which I thought was pretty cool. I didn't think there were any elite courts though. I think I liked a school gym the most and spent most of my games there. The problem I have with this game though is well, first of all I don't like Barry de Jay very much but he's in both of them, but in 2004, he gets more a humor in this one he just seems like a harsh mule. It was fun seeing the interviews after each post game though, shame they took that out in 2004. The other problem with this game for me personally is out of every single Backyard game I ever owned, this one would freeze up and give me that blue screen error more times than any other put together.
Backyard Basketball 2004: So, I like this out of the two options to Backyard Basketball. I never played 2007, and don't plan to because I know that horrible era is. The 3D looked really good in this game which is kind of strange how Backyard Football 2004 wasn't able to get this one right. And of course that awesome Humongous Rectangular Gardens can be unlocked and played whenever you please pretty much clinches it.
Backyard Hockey: I remember getting the original for Christmas and literally spent the entire day on the season and actually finishing it. I do like some things about it, like when you create a custom player, it actually saves that custom plater, but 2005 is just so much better in my taste. But still on this one, one thing that bugs me is 3 minute periods that can be too long because you can be winning by so much. There's also unncecessary too hard shots that will make the puck go all the way around the rink twice.
Backyard Hockey 2005: This in my opinion is the best Backyard Sports game out there. I love the added logos on the jerseys, the names behind that jersey, the 3D enviornments, the Tibeti Yetis, the mascot at Tech State U, oh you name it. The only thing I dislike in this game is you can't save your create a character. If you always want one, like me, you have to continue on making one every season. It's also fun playing with the camera angles and give you a different perspection of the game. I've been playing this since it came out, and I plan to play this as the years go on. Terrific game.