I am a big fan of Nelson Pass, but his Class A amps put out LESS as the speaker impedance drops.That’s silly, and it’s the antithesis of a Class A amplifier design. Anyway, although the Pass may not be the space heater the Krell is it’s still gonna generate a good bit of heat so not sure how much you’re really saving going that route. But I’m sure it’d sound great with the Pulsars and probably would be more to your liking than the Bryston given your tastes and familiarity with the Krell..
What I’d consider doing with your budget is buying a used McCormack DNA 0.5 amp and send it to SMcAudio to have Steve give it the full upgrade treatment. I think it would make the Pulsars sing and put out a lot less heat than the Pass. Just another option to consider and best of luck in your search. Love the Pulsars BTW.