Madfloyd, MDF does not make a very good platform, though I doubt it would suck the bass out of the system. It will make for an uninvolving sound however. Maple makes for a good platform. I use a maple platform on a sandbox with a separate platform for the motor. I agree that the platform material makes a difference in sound.
I do not agree that the upgrades are necessary to get good sound from the ScoutMaster. Mine is relatively stripped down except for the signature arm and I have never had the bass problems you are having. AAMOF, the bass response with the Dyna 20xl was superior to that of my cdp which is known for its bass qualities. This is what makes your problem hard to diagnose.
There are those who do not like the VPI sound. But it is usually a PRAT issue rather than bass or midbass. AAMOF, I think that VPI is somewhat known for its bass response.
I do not agree that the upgrades are necessary to get good sound from the ScoutMaster. Mine is relatively stripped down except for the signature arm and I have never had the bass problems you are having. AAMOF, the bass response with the Dyna 20xl was superior to that of my cdp which is known for its bass qualities. This is what makes your problem hard to diagnose.
There are those who do not like the VPI sound. But it is usually a PRAT issue rather than bass or midbass. AAMOF, I think that VPI is somewhat known for its bass response.