Interesting post and before leaving my comments I have to totally agree with Hayabusa1021

*
NES: Without a doubt this is my main console for collection purposes and even when there are so many awesome games there are crap titles too, don't want to collect all of the cartridges, my policy here and my first priority are those games that I played as a Kid, then those that are becoming rare but not only because it's rare it means that I'll purchase, those that are pure crap like The Cheetahmen will definitely won't be here, and for the rest if it's good and the price is accessible it will be added.
*
Playstation /
Playstation 2: Almost have all those games that I wanted to play with some little exceptions most of them from Capcom like Dino Crisis 2, Strider, Strider 2 and some fighting titles like King of Fighters XI also some Japanese releases, already have an Action Replay system and with this one I can play these ones where my main goal is the fighting Sengoku Basara X Cross.
*
GameCube: Same as Sony consoles where are some titles that need to have them but they are not that important like Mega Man Legends where already have almost all of the games at the NES, priority here are familiar games and those that I can play with my daughter like Mario Party and some sports exclusives with Nintendo's characters.
*
Nintendo 64: There are only one priority here and it's Conker's Bad Fur Day and that's all, don't get the wrong idea, there are so many awesome titles here but most of them are first person titles and since I have a vision problem that make me sick every time that I play at least the 90% of the time these kind of games.
*
Super NES: Priority here is like the NES and because it's another of the consoles that I played the most as a kid.
*
Wii: This is the one with less games and even when they are some exclusive titles, the priority here is only those games that I see at the reviews and I really like them also some that my friends told me that I need to purchase.
*
Game Boy /
Game Boy Color: Again don't want to collect them all, this isn't Pokemon you know, priority here are those fun titles and those from the genre puzzle, why ?, even when I have the Super Game Boy I do enjoy a lot playing with the real thing, it bring me a lot of awesome memories back every time so if the game doesn't have these requirement I'll wont be added.
*
Nintendo DS: This one it's another one at the bottom of the priorities list, just need if am not wrong at least five titles, purchased this one just for some exclusives titles like The Legend of Zelda, Mario Bros series, most of them from Nintendo.
*
Game Boy Advance: Only need two titles, priority here was purchased the same day as this one.
*
Dreamcast: Those games that I tested with the copies of the GD-ROM and I totally felt in love with them, like Canon Spike, Shenmue, Soul Calibur and maybe some others, priority is not the big deal here since there is always easy to play them in the original console, sorry but it's true.
*
Xbox 360: This one was purchased only for the Gears of War saga, priority here are just those titles that have boobs and blood but in my personal opinion they aren't that much, at least 10 more.