I really dislike the "cultural" trend of wanting everybody to be more equal at combat (more precisely, at offense), then wanting everybody to be able to heal, then wanting healers to be able to heal without sacrificing offense, then wanting everybody to be equally useful out of combat etc.
This trend kills diversity, which decreases the importance of strategic/tactical choices and teamwork, and for my own tastes this means the game to become less interesting (I do understand that one reason for this trend is the proliferation in the last decade of "bedroom players" i.e. players who spend most their time thinking about their PC alone, want it good at everything, and even don't fully tolerate being part of a team).
I prefer the simplicity of: add a Fighter to your party to increase your offensive power, add a Cleric to your party to increase your healing power. A Fighter makes your "output damage" significantly increase (your party kills opponents faster) while a Cleric makes your "input damage" significantly increase (your party is slower to be killed) -> strategic choice.
It's ok that the Cleric traditionally isn't bad at output damage too. But for my tastes it sucks to hear people complain that "I have to waste my attack to heal a friend". It's a trade-off, either spend this round increasing your "output damage" or decreasing your "input damage" -> tactical choice.
If replacing one non-Cleric with a Cleric makes encounters clearly easier, then there is something wrong with the game design, which must be fixed. There really shouldn't be one strategic choice (having a Cleric) which dominates the alternatives, because this really means you have no choice.
