At 135 for you I would continue to hoard until there are two good 5*s to pull for.
My Kitty is fully covered and I love it but Cable is my only other covered 5*, with Kingpin being one cover away. It also took me far more than 135 total pulls.
this is the same situation I’m in - i have 330LTS and around 600cp.
im thinking about covering kitty as well, but the two 5s before and after her are… not what i, personally, expect in a 5.
it took a long time to get 300+cp, i won’t waste that on one good and two underwhelming 5*s
Hoard. It’s better to wait it out a long time then to go into 5* land unprepared. Wait until you have 300 covers and there’s at least one OP 5*, preferably meta defining.
Also I’d BH 4*s that currently feed meta defining characters:
Valkyrie > Thor
Shuri > Okoye
If you already have some covers in one or the other, focus that one first.
It’s unlikely you’ll get to be able to champ them before you’re into 5* land, but better to get working on the OP ones now so that when they come into special vaults it’s easier to finish them off.
The real game has nothing to do with 3 match, the real game is roster strategies and trying to beat RNG.