I am more mid game than end game and have found the proving grounds to be appropriate in terms of challenge and pace. I am just glad we are given a shot to get the conquest characters at all. I have obtained, Razors Crest, CAT, interceptor and Maul through proving ground and am close to the rest in varying degrees.
Having proving grounds removes the pressure to some degree to having to max out conquest all the time. Its nice to know you can get them if you don't go hard in conquest (not one my favorite game mode, a necessary evil IMO).
