Gems and alts what is best

ive 2 chars at 1490 with lvl 7 gems,
ive 2 other alts at 1467 and 1450 with lvl 5 and 6 gems

do you think i should be using my new gems to push for level 8 gems on main to be able to do new content or push a 3rd alt to lvl 7 gems?

i’ve been going for full 7’s first then slowly upgrade your mains gems etc

i do slow grinding step by step. At beginning i had full gems 7 on mains and full gems 5 on every alt , now i have one gem 10 and one gem 9 on main and slowly gettin gems 7 damage only on every alt. Then after i get a second gem 10 on main, ill slowly give gems 7 to alts in CDR.

Im trying to push everybody in that but with still my main first priority