So I just got a 3ds, and since there aren't too many games out for it quite yet, I thought about trying to get into Pokemon. The thing is I'm a completionist / crazy person and if I start down this path, I want to be able to collect as many of these guys as I can as a long term goal. I did some research this weekend and found out you start with the generation 3 games for GBA, then you can transfer those between each other and then onto generation 4, and then from 4 to 5, which is the latest one.
My main question is once I go through the GBA games, which are cheap enough so I don't really mind getting all 5, would I have to get every version of the DS games? Or does the games' online trading capabilities alleviate that need, such that I could just get, for example, Platinum, Soulsilver, and White, and be able to fill in the gaps? I have enough old Nintendo equipment that I could do my own trades but I don't know anyone else that plays locally. If I could save myself a little time and money if some of the games are identical except for exclusive Pokemon, I'll do that. If the games themselves are different enough though, I'll play through them all. Like I said, it's a long term goal.
Question 2, how hard is it to find the limited special event Pokemon on the online trading system? I'm not too concerned with those if they're too rare, but it seems like Nintendo adds ways to get older ones every so often.
Lastly, what's the best order to play through the DS games? I know probably for GBA you play Fire/Leaf, then Ruby/Sapphire, then Emerald, but I'm a little lost after that. Thanks.