There is no such thing as a "low maintenance" phono record playing system. The record album itself needs constant TLC. You do not just take it out of the sleeve, drop it on the turntable and drop the tonearm to play. Contrary to what you stated, a suspended sub-chassis platter needs adjustment only after years of use, usually less frequent than tonearm tuning and much less frequent than record cleaning. Yes, it does need tuning.
You are right about a direct drive turntable motor. Once the motor bearing wear becomes audible, there is nothing you can do but to buy a new deck. I consider a turntable, tonearm and cartridge combo to be in mid price range when it total about $6000 or less, with 1/4 to 1/3 goes to the deck. This is by no mean high end, but more like mid fi. The cartridge is usually the most costly item with the tonearm comes in next. I spend money on equipment where I can hear the most difference, as in this order.
Also, not all belt drive turntable has suspended sub-chassis platter. Rega turntable is one of the best example of a rigid deck without a sub-chassis. The choice of a turntable is very personal and subjective. If you like your Technics SL1200/SL1401, it is wonderful. But take care of your record album too.