How big is your hoard?
It is not advisable to level up a seven cover fivestar, so you really should aim for a nice hoard, then bust it when the Latest Legends setup is favorable. Of the fivestars available now, Thor is good, Archangel is very niche, and the jury is still out on Ghost Rider. It is probably good to wait at least until Archangel leaves the token pool to bust the hoard - you may get a decent Thor but won't be able to give him many champion levels as he is leaving the token pool in about a month's time.
Of course, it also depends on what the future fivestars look like too. You may need to wait a while for the next Gambit, sadly.
OneLungDave said: My hoard has 75 LTs and 2500 CP. I guess my question is more focused on leveling or soft capping the 5*s. I'm not looking to champ any of them. I'm wondering if leveling them to say 275 or so is worth it - just for normal gameplay and increased roster usage.
Doesn't really change the answer - most fivestars need covers to be effective these Days. It seems to be possible to level up a fivestar to level 350 without noticeable effect on your PvP MMR, but I am unsure if you can do it with multiple fivestars or if it just works once. As long as their base level doesn't exceed the level of your boosted fourstars you will probably be fine though, but the MMR jungle can be tricky to navigate...
175 pulls is pretty decent though, it means you are well over halfway to 300...
carrion pigeons said: In general, is there a level you can bring undercovered 5*s to that will make them a bit less awful in PvE while not impacting your MMR?