Once upon a time most of these figures would have been picked up by local retailers, but for whatever reason that eludes me it doesn't seem to be happening with these store-exclusive Siege figures.
But even all of these store exclusives appear to be repaints and/or retools of pre-existing moulds, and again many of them are based on fairly obscure characters (with characters like Ratchet and Skywarp being exceptions).
Although if you're looking to build a CHUG collection based just on characters who appeared in the G1 cartoon then you're at a considerable advantage. Not only do you have fewer toys to collect but also most of those characters have already been done as CHUGs anyway. Obscure and generic cartoon characters aside, we've got...
* Season 1: all done
* Season 2: all done
* Season 3: almost all done; there are a few outstanding ones like retail CHUG versions of the Battlechargers and... that's it
* Season 4: most done; we need the remaining Throttlebots, Autobot Targetmasters, Headmaster Horrorcons and Scorponok
So as far as the Anglophone G1 cartoon is concerned, the overwhelming majority of the cast already exist as CHUG toys. You're just filling in a few gaps now with the latter two seasons.