This might be helpful:
It isn't the cleric class you need to get rid of. It is the healer role that would be great if it were optional.
That is: freed from the often implied assumption of taking the healer role, the Cleric is a fun capable class with great offensive and defensive capabilities. It certainly does not need to be removed from the game.
What you do need to change is this: instead of relying on a central source of healing, you need to distribute this healing power over the entire group.
To deconstruct the problem even further: the issue is that one player takes the damage, but another is expected to sacrifice his action to heal that damage.
If each player instead becomes responsible for healing their own damage, the "unpopular healer" problem would go away - no longer can the Barbarian keep axing down foes expecting somebody else to service his hp pool while he's at it.
So. What you need is enable all characters to use up their action to heal. Either themselves or their ally.
However. What you don't want, is to fall in the 4e trap where each party member had exclusive access to their share of the group's total healing power. Why? Because that meant each party member needed to get in there and soak damage!
This absolutely destroyed the entire idea of being a "lurker" or "artillery" (to borrow 4e terminology) - being the archer, the wizard, the assassin etc that wants to stay at range and avoid melee (unless at your own terms). This didn't work in 4e, because not getting in there and taking hits meant that perhaps your most valuable resource wasn't used: your hit dice.
So. A suggested solution:
1) Pool the entire group's Hit Dice. (perhaps use poker chips and place a pile of them at the middle of your table)
2) Give all player characters the ability to spend their action to use up to their level in Hit Dice to heal themselves, or half their level in Hit Dice to heal somebody else by touching them.
Supplement this by not being stingy as DM with healing potions, and you should be able to explain to your players that they no longer should assume somebody else will heal their wounds.
Instead everyone shares in the fun of taking offensive actions that kill your foes. If you get hurt, you are primarily responsible yourself for healing that damage. That is, if it makes sense for your ally to help you, that's fine.
But no longer can you get pissed if the "party cleric" rather kills some goblins rather than rushing to heal your wounds so that you don't have to stop killing goblins yourself!
[emoji3]