So much in 5e depends on how you expect to play. Regarding the concentration thing for example, in most previous editions you could bust out a spell, or in 3.5 a ton of spells, wade into combat and go for it. My players were used to this, but once they worked out how concentration worked they adjusted their tactics. The key thing if you are buffing someone now is not to get hit yourself. It changes the way you play, and the self buffing classes need to expect their buffs to drop more often. As a side note it makes potions way more valuable (assuming I am running them right) as they appear to not require concentration.
Also it's pretty easy to drop the taking damage part from concentration. You could also house rule that the casters ability score modifier could be their maximum number of concentration spells if you want more "buffability" in the game.
Also since the bad guys buffs drop pretty easily as well I am finding I am having them disengage and rebuff themselves during combat.