It could be good, and if it’s anything like Strange New Worlds it will be, but dropping them back to the main timeline still means that the bridge crew can’t die. There was an episode early on in Strange New Worlds where I think it was Spock, Uhura, and another crew member were in danger. We immediately knew that Spock and Uhura couldn’t die or be seriously injured, and it took a lot of the tension out of the episode, for me at least.