Well, make up your mind really. On the hand you're kinda insulting ("all my work moving to Joomla has likely been wasted for choosing K2 to migrate to") and then it's "i'm stuck with you guys".

K2 is indeed a flexible content tool, much better than Joomla. Always has been. But it *may* need capable hands as well. And no, reverting back to Joomla is not an option because Joomla changes it's database every couple years whereas we were smart enough to do a proper database schema more than 10 years ago.

Aside all that, if you're not interested in digging more into how things work and most importantly, if you don't have the patience, you should consider something like WordPress with a drag and drop builder or something. Whatever works for you.