Revisiting Tube Recommendations for Cayin TA-30

My appologies if this has already been beaten to death! :)

I hope you all are up for this post! I'll owe you all big time!

I have a Cayin TA-30 (purchased in '03) with mods from Paul that included the sub out. It has been connected to B&W Nautilus 803's and a B&W ASW800. I have a Sony XA9000ES as my cd/sacd player.

I replaced them all once from Paul with EL34's, 12AU7's, and 12AX7's tubes, from EH. Simply put, the TA-30 just doesn't come close to sounding as good as the stock tubes did. It, to me, sounds so flat and not open like it used to. I bias the tubes about every 90 days to keep them running at their best.

So now come the questions.

1st. The broad question I have is I need to replace the tubes again, and I want to replace them all, but there are soooo many options and choices and I'm really not interested in "tube rolling", though I know I really should be. Where does one start? I'm overwhelmed!

2nd. The TA-30, I see, can accommodate my types of tubes. Is a KT88 "brighter" or better, or should I stay with EL34's like it's called for? Should optional tubes be used on the front end? Is the TA-30 "pushed" to much using these other tubes?

3rd. Since I have the TA-30 connected to the sub, should I focus only on mids and highs for tubes?

4th. Is there a source out there where I can get this information without bothering you all? I googled some variations, but just haven't had luck. Is it just me, or are all the tube reviews done on guitar amps, not home audio amps?

Well, wasn't that a mess??? :)

Thanks in advance to you all! I hope this thread can become a resource for all us TA-30 users!

Regards,
Bob