I feel that this is an opinionized question, but still; Is it smart to keep a Pidove/Tranquil/Unefezant in your main party? Or should I replace it with Zekrom/another Pokemon?
almost ANYTHING is better than Pidove line. So no, keeping it in the party is NOT a smart thing to do. Replace it with Zekrom or something else.
This isn't a big deal, but I was just wondering how Unity Tower keeps track of all the people you traded with. I know that my white version has a mix of people I've traded with through the WFC & the GTS, though it doesn't have all of them
There's a limit of 5 people per room, I think it only keeps the latest 5.