Kael can be really punishing in low elos, that’s true.
Thrall, Valeera, Mura are also great imo for that setup.
But Auriel is still quite battery dependant and you can’t carry well with Healers (this is true to Uther as well). Ofc, your team needs Healers, so respect if you fill for your team, but those Heroes (and Maiev) make your really team dependant.
For Healers, I’d suggest Khara and Rehgar, because they can do camps, deal dmg and still heal enough to save allies from misplays.
Ragnaros, Azmodan and other PvE heavy Heroes can also do a lot of favour for you.
When you need help, feel free to ask for builds here and post replays and ask for advice here.