I didn't look into it much, but I would have thought the sprout's analog out would be variable, not fixed. Partly why I wrote "*could* you use the sprout as a preamp...".
Anyway, as Erik says, remote control volume is almost essential!
Disagreement in the audio community? How unusual.
I'm fearful of commenting in case I get roasted...
"..the extra watts might make the music ... sound better"
The general consensus, as I see it, (and note that this is also a general statement!) is that a more powerful amp is often better equiped to deal with sustained power draw, e.g. lots of bass, and large dynamic changes. It may also have better 'control' over the speakers, particularly the woofers, meaning it's better able to start/stop them quickly, resulting in 'tighter' bass.
It's also suggested that such an amp, at lower listening levels, is able to more effortlessly drive the speakers, giving an overall fuller sound at low listening levels.
There are obviously exceptions and nuances to what I've written.
Tube amps are generally quite low in pure wattage output, but can sound fantastic and easily drive speakers to loud levels.
Watts only don't tell the whole story.
I'm sure you've done lots of your own reading, but seeing as you have a sprout, let me point you at a very short PS audio article on headroom.
As for will a 100w a/b amp sound better than a 32w d amp... I'm not sure anyone but you can answer that!
I'd hate to say yes, then you buy one and not like it, and vise versa; especially never having heard either!
Don't know where in the world you are, but schiit do home trials for 5% restocking I believe. Might be worth a shot.
Although your remote volume requirement might need you to rethink the vidar.
D6jg - "forget about any further expenditure at this stage." Where's the fun in that?!!!