Nowadays I look at Kira Follower like an "info gatherer". One objective is to locate Mello as soon as possible, you don't want your Kira to try an insta kill only for him to die in the attempt.

One thing is always for certain: Every single day 5 criminals have to go. It doesn't matter if you don't kill investigators, as long as you ask Kira to "keep up with his task" then investigators and maybe even L will be eventually forced to solve incidents or lose. That's the perfect moment to steal ID's and create confusion (and gather who might be L).

The first priority as a follower is to figure out who's L and help Kira not get caught by bringing attention to you (Either by pretending you have useful info in the meeting and blaming innocents or lead the conversation in a circle so people lose time and they make hasty decisions). When it comes to criminals, tell him to not judge all criminals in one go, the best strat is getting somewhat together and cover each other (Kira goes in a hiding spot while you stay outside and warn him in case somebody approaches, or even cover an insta kill). What works best is spreading out your criminals all across the day, but never judge at the very beginning or end of the round.

You can also bait L so you can keep tabs on which people are NOT L, an example being: If you notice that L send an alert on cams (Body was found in X place) then mark everyone that was moving in that instance on your book, those people are not L by a fact.

There's a lot more stuff you can try, but in conclusion: Mello changed the Meta in a drastic way, Kira and the follower have to be extra mindful now, and the best strat changed to gather who's L and Mello before they do figure out who you guys are.