1) What other people do you want to be a part of this from previous arc?
Maybe Weevil? Though I'm not too keen on that. It's already the former Shichibukai crew, but I feel adding one more just makes it stupid to me and I really don't know why, lol.
2) Particular people they assign bounties to and the amount?
The most important ones will be the Admirals and, I imagine, other Yonkou and their crews. Makes snese given that they were already hunting pirates before. Now with the run to One Piece about to really kick off, it'd make sense that'd they double down on Buggy's rivals. I think the pirates will keep their bounties as is, but the Admirals and a few key marines will probably get bounties 2 billion+ at the least.
3) When are they active participant in the story again?
Should be fairly soon. Would honestly be a good time to pay off the whole Captain John's treasure map as that could potentially be an alternative to the Poneglyphs. At least, it would get them up to a point where they can basically mooch off of everyone else's directions.
4) How do you like this new development?
Fun and partially expected. Mihawk, I figured would end up joining someone for the last run. Didn't expect it to be Buggy and didn't expect Crocodile to join in.
Coby has never been powerful in the series
Last time we saw him, Coby was impressed by Kyros's Haki.
If Coby was a pirate, his strength would be worth 100 million at best.
Eh, I think this is underselling him a bit.
Koby isn't raking in the feats, but, despite his late start, he's shown to have a rather impressive growth rate somewhat similar to Luffy. Not on the same level, obviously, but still impressive enough. Given that he's hanging in the New World and a member of a specialized Marines Unit, I'd say that's enough to give him the benefit of the doubt in terms of strength. Not saying he's worth a Billion, but he's certainly worth more than 100 million. I'd say 300 million is the least he'd earn.
He was impressed by Kyros, but Kyros was also impressed by him and praised him for some of his off-screen endeavors. Whatever the Rocky Port Incident was, it clearly was something of note as it gave both him and Law notoriety.