JS,
4425's suggestion was good to me: Naim has made a lot of Naits (Naim Integrateds) and in your case I would suggest two very different solutions: a Nait3 – could take some time to find one on the 2nd hand market, but complements your CD3.5 perfectly, is a lively and serious little amp that drives anything, just leaning on the 'cheerful' side; or a SuperNait, first generation: it is solid and authoritative, can be found for very reasonable sums and has a more than decent DAC on board, that might come in handy sometimes.
As an alternative, a Nait XS, a little more mannered and shy in the bass but with a great capacity of looking into the inner details of music.
I have been a Naim user for decades so sorry for my monochromatic replies...
Max