Every healer player I know feels the opposite. Healing Words helps healers be interesting to play, by allowing them to heal and do other things.
Back in 3e, I ran a high level one-shot for my players. The encounters were hard. In the first encounter, the cleric had to spend the first three rounds healing dropped PCs. He could use heal but still had to spend a move action (in his heavy armor) to get to the downed PC, spend his standard action to cast the healing spell, and also used up that spell slot. Both of those latter two resources (action and slot) could have gone to something more interesting.
On the fourth round the PCs finally dropped enough opponents to relieve the pressure a little bit, at which the cleric started dishing out the destruction spell and bringing his fatal divine curse unto the enemies.
I'm a fan of 4e's style because the cleric is no longer "screwed" by having to spend those resources.
4e introduced whack-a-mole healing, and 5e didn't get rid of it. 5e is a different game; it should only incorporate parts of 4e that make sense to 5e.
I saw a more generic form of this idea from @Garthanos and I thought it might make an interesting house rule for healing word.
Healing Word: (remove base healing). The target may spend 1 hitdice. For every level above 1st this spell is case, the target may spend an additional hitdice.
A nice way to make the spell a little more costly as it pulls from your "reserves" and puts an implicit limit on it. This contrasts with cure wounds which is "endless" magic but slower, which seems a nice differentiator between the two.
Regular Healing Word:
A creature of your choice that you can see within range regains hit points equal to 1d4 + your spellcasting ability modifier. This spell has no effect on undead or constructs.
At Higher Levels: When you cast this spell using a spell slot of 2nd level or higher, the Healing increases by 1d4 for each slot level above 1st.
This would potentially heal more but be much more expensive for the target.
I note that neither Healing Word nor Cure Wounds have a Hit Dice cost as written, and low-level PCs have very few hit dice, one per level. (Contrast with 4e, where your HD value will increase, but any character who doesn't increase Constitution or spend specific feats will not see an increase in the number of HD.)
For the house rule to work, PCs would need more HD at low levels, and perhaps not gain an HD every level. Or perhaps use some other resource. You could literally make a new one as part of the house rule: a character cannot receive Healing Word more than X times per day. Upcasts cost extra resources.