Is there a class your eager to try out in the new rules?

[Oramac]

Even if they made base DS not a spell, it would probably still take a bonus action...

For sure. I'm totally ok with that. I just have issues, both mechanically and thematically, with base smite being a spell.

I have to admit, Wishing for the UA version of a feature is novel if nothing else

Not something I'd thought of before now, but certainly intriguing. You'd need a really kind DM to allow it without complications, but I quite like the concept.