They should only be added after the season including them is over. Considering we only saw a good proper look at Hunter in the trailer. Wrecker, Tech and Crosshair are not seen at all. Models won't be created for them until after their debut. So I would say wait until they actually have been released and have a stable model pack.
BUT: Having Bad Batch being added into lore and possibly even the server would bring back quite a lot of players to many SWRP servers because of all the hype and the hopes of one day becoming them. It would be a really good addition for the servers sake.
So, +1, but only after Season 7 has ended and the hype of Clone Force 99 is taken to games ie Gmod. After the season there would most likely be a lot more players looking to play SWRP or return to SWRP etc.