Not more than 250 / 350 actions are recommended a specially after IG the last updated on Feb 10.
You have answered yourself. 60-70 likes it's the top for now, use that as settings and increase slowly after 1-2 weeks. I would start with 40-50 likes than 2nd weekd - 50-70, 3rd week 60-70, 4th week 70-80 likes. Play with the numbers and find the threshold, when you find it don't go for maximum, do it lower with 10%. You don't want that IG algorithm to be triggered all the time when you reached your maximum.
Altogether Follow + Unfollow + Like + DM not more than 250-350 / day?
So the limits go up with age of account then?