An HE would certainly be an option, or maybe a Nova PE. Adding a 250 to the Nova may not be what you are looking for in terms of a big uplift. I should say I haven’t heard the Nova or Nova PE, but I do have an Atom HE with 250.2.
I am guessing you don’t have a dealer who could let you discuss/demo or home trial these options?
Bruce
As the OP’s plan is for a 333 and 332 in due course, it doesn’t make sense to swap the Nova at this point. Adding a 250 seems a sensible step in the process, even though it’s unlikely to make a significant difference to the performance of the Nova.
He could sell the Nova for $3,500-4,000 and buy a second hand Atom HE for $2,000 and acquire better SQ in the process. I’d say that makes a lot of sense. The Atom HE is also a better match due to the XLR output.
Naim Nova second hand prices have come down a lot. one on facebook has just been reduced to £1899.
I’d really want to demo Atom HE/250 vs Nova/250 to be sure that it was worthwhile. As HH says if the end goal is 333/332 in fairly short order then might be better to stick with the Nova for the moment and save up the pennies.
Bruce