I have gone through a few really nice EL34 amps, and then got an eye opener from the 6L6 family. While older G and GA types are a bit on the 'spensive side, NOS 807 and Svetlana 'Winged C' 6L6GC are nice valves in the cheap end of the pool. There are *MANY* good sounding valves in the cheap end BTW.

For low NFB designs, I got a really nice design from Heyboer. It's a copy of the Peerless S-265, a 20-20 Series, 10k:16,8,4,2/40 Watt design with a core bigger than the Dynaco 60W Mk.3 design. The winding design leaves it really easy to put U-L screen taps where the design calls for them( semi-custom designs do have their benefits, No? ). Or putting in more than a single pair of taps if you want to experiment a bit. No matter what sort of religious dogma might be heard about winding OPT's, it isn't all that dificult to get a good design.

Just pick a design which can be used in a few different circuits. For example the 265 can be done with 807's, 813's and GM-70/845 designs. If proper care is taken, silly B+ is not required, and 40W is a lot of power if you have efficient speakers.
regards,
Douglas