McIntosh MA-230 rebuild project

Hi All,
I know some you will say this amp doesn't sound so great.
I also wonder how it compares against my former Eico ST40 and ST70 amps of many years ago?
Being that I acquired one for very little coin, I figured what the heck. Does any one have any suggestions or links as to what can be done to improve it's sound qualities?

Currently I need to replace the 4 7591 and a trio of 12ax7, 12au7 & 12at7 tubes.

A good place to start & replace the ? tubes with recomended brands.

I'm expecting to also need to replace a handful of caps. After that it's open season..

Fwiw: I plan to bi amp the system with a ~ 200 watt apt-1 to drive my 12" sub. Main's will be Mini Advents.

Ideas any one?