budget diy tube preamp beating many expensive preamps... problem with my system?

YOu do have some red flags in your system, especially the power strip.  I doubt you are hearing anywhere near the capability of your amp.

that said, a simple tube system will often outperform a complicated integrated circuit with swiss army knife features.

Jerry

What 6V6's have you tried?

Couldn't find tube rolling info for the Moreplay.

DeKay

Try buying decent cables,the Wireworld Eclipse is a excellent cable

snd is built better then most  at 2x its cost.and better parts quality.

I’m sure my heavily modded phono preamp sounds better than many models three times the price. The price doesn't guarantee sound quality.

Don’t underestimate a DIY amp, properly designed and built.

Especially Bottlehead.

Not paying for the distribution network, a fancy box, or the labor to assemble it.