Blistering pace of raids is too much

Depends where you are in the game.

Us Endgame users its no issue as all new toons go straight to 7* R7, not so much if in early or mid games.  More rewards for the investment, everyone else can do older raids, or get lower rewards in the new. Its not like the new toons won't be used in other modes either.

Also it should be remembered that even though the legacy raids are easy now once they were difficult if you didn't have certain squads. The R8 mat Rancor one was totally unobtainable to our guild at the time,  sometimes you just have to accept your account isn't ready for some things but it will improve over time.