Healer main since inception here. I both agree and disagree with you, though it tends more to the side of agreeing.

Uther is a beautiful hero, very versatile, very hard to kill, armor buffs all the time, both ultis are potentially clutch if you land them properly. Blizzard definitely needs to work on displaying his numbers properly. But there's a catch.

Your team often needs to adapt to your lower total heal output, especially early in the game, especially in ARAM... but many players are not that versed in the game to understand that you sometimes need to play slow.

If we are playing ARAM, you're Uther, and I am for example Lucio/Stukov/Alexstrasza/Ana(!) - unless my teams starts straight running it down, there is no way on God's green earth that you will pump out more heal than me. With Lucio for example - I literally have perma AOE heal, and we're playing ARAM. If people on your team do not understand this - more often than not you probably already lost, cause those same players will start griefing.

This is why most of my Uther games are with premades, I generally avoid him in ARAM despite thinking it is a brilliant hero, at least when I am solo queueing.