Many different points of view. I will add a few of my own for the OP.
--a kit would not typically be a big factor in my decision making. Why? Simple. The markup of amps from Elekit, Analogue Ethos, AK kits from kit to pre-built is actually small and insignificant (a few hundred dollars) and if you factor in your time I do not think you are saving much. Now, if you are into many upgrades/mods, if you love the satisfaction/nostalgia of kit building--go for it!
--one poster states that low powered SET amps, even with efficient speakers, are a no go. He knows more about tube amps than I ever will. But I trust my ears. In my secondary system, I have a 4wpc SET driving Omega speakers. Especially since I added a small pair of REL subs, I am shocked at how much of my music collection sounds great on this system. Also note, I run the Omegas full range with no crossover and these are in a fairly large room. Does it do everything my high powered primary system does? Of course not. But 90% of my music sounds so good on this system I could be happy with this for the rest of my life. In fact, some of my CD’s sound better on this system than my main system.
--speaker/amp matching is critical with SET amps. In this setting, full range drivers are a natural choice IMO.