So… once you pass into the 5* realm… an odd thing happens. Your 3* roster becomes more important than your 4* roster… and your 4*s become largely irrelevant. I’m primarily speaking about PVP, but it happens to a lesser extent in PVE as well.
This is partly because there is such a gap between 4* and 5s. Some of the 5 (Iceman, for example) come close to 5* level when boosted if you have added a significant amount of champ levels to them… but for the most part, even a boosted 4* doesn’t win a spot on the team over a 450+ 5* in normal PVP. This is the way the system is designed, and I highly doubt it will change.
The other reason is the lack of 4* feature events in PVP (other than release events). You are locked into using a 3* in PVP, so if that character boosts up to 390, that’s a HUGE advantage over one that you haven’t champed and maxed. So it still pays off in PVP to have a deep 3* roster of highly-leveld characters. 4*? Not so much. Honestly… not at all for me. This is something the Devs could change… I still don’t understand why we aren’t seeing the non-release 4* feature events.
I said this is primarily a PVP phenomenon… but to be honest, I hardly ever use 4s in PVE as well (outside of heroics and essentials). Again, my 3 see more action than the 4*. Reason being, the 3* tier has, in my opinion, better support characters than the 4* tier. There are 3 primary teams that I use in PVE… all of which revolve around a 3*:
SWitch, GG, Phoenix
IM40, BSS, Phoenix
IF, OML, BSS
I don’t know if anything can be done about this, other than releasing 4* with better support powers to complement the 5s… I am mainly pointing it out because I think it’s odd that the 3 (rather, a few 3*) remain relevant longer than the 4* do. (And yes, I know there are solid 4* out there… PMax, XFDP, Quake, etc that work well in PVP… I just find they don’t work AS WELL as the 3*s)
Bottom line: In one humble man’s opinion, we need more 4* feature events in PVP (really we need more event variety in general, but that’s another soap box). And it might be fun to add some “support” characters along the lines of SW, IF, IM40 to the 4* ranks.