Ok - Former Roadster and multiple Fender Hot Rod Deluxe owner here. I'll do my best for you...
1. I had the Roadster head vs the combo. You can try taking the back cover off, but I would also recommend trying an external cabinet (maybe a 1x12 of your choice) just to see if that makes a difference. If volume is an issue, I would recommend an attenuator.
2. I'm not good with replacing things like the fans, so personally I would leave it alone. But I am sure there are plenty of quieter fans out there if you feel adventurous. Maybe call Mesa also and see what they recommend?
3. The Roadster clean setting was definitely tricky for me also. I play Schecter guitars with hot pickups, so there was definitely a sweet spot. If memory serves, Gain was at 9 o'clock and then I used the Master/Solo/Output knobs to do the rest. You might want to ditch the V30s also. Personally, I prefer Mesa C90 Black Shadow Speakers vs the V30s. Clean tones are WAY better sounding and there is none of that V30 nasally/brittle hump. You might want to check out the Warehouse Guitar Speakers also - they do a V30 clone that is supposed to be smoother, but I've never used it. I've been using C90s for almost 20 years.
a. To answer your other question, no - it does not do Fender cleans well. Maybe if you use a really low output pickup, but otherwise no way. In the Mesa amp timeline, this is where the Lonestar and Mark V stepped in to provide better (and closer to Fender) cleans, in that order. If you want pure 100% Fender cleans, get a Fender amp. Or something like a Quilter Reverb 101 head - pretty close to clean Fender tones also (I have that one and love it).
b. I've never messed with biasing Mesa amps, so I cannot comment. I purposely buy Mesas to avoid all that crap.
c. It sounds like you want Fender Cleans and Mesa Metal. You might want to try one of the modern Rectifiers - if you can find one right now (my new Dual Rec is on order til August) - the clean is supposed to be much improved, even compared to the Roadster. Otherwise, get something else that emulates the Fender (again, I recommend Quilter 101 Mini Reverb) and keep the Roadster.
d. Yes, for all intents and purposes it sounds normal. Once again, it's not a Fender/Mesa combo. They don't exist.
You also tried the Marshall JVM series. I used to have the 205H and for metal it was just molten sounding. The cleans were meh though. For me, I found the Mesa amps to blend better with other instruments, but ymmv.
Good luck - hope this helped.
