In general, I find the Shuguang tubes in the Jolida to give the amp a slow, recessed sound.
For the power tubes, either Svetlana or JJ tubes are a worthwhile upgrade. Despite what Jolida has said, I really like the JJ(Tesla/Teslovak) E34L in this amp. I find it is an excellent EL34 in general, and really improves what is already a fantastic amplifier. The Svetlana are more warm and lush to me. The JJ are more open and fast. I don't have any experience with ElectroHarmonix EL34, but perhaps others can submit an opinion.
Anything that you go with from Europe(current or NOS) or USA will be an improvement over the stock input tubes.
You really can't mess this one up.