Welcome to flyertalk. Interesting and provocative first post. One of Delta’s key market differentiators is the UDU. There is history behind limitations on upgrade fare classes, see saveskymiles. In building the current business model, Delta has recognized the importance of loyalty through the different levels of SM and the corresponding perks. These include access to upgrades at earlier time periods. From your post you seem to be dissatisfied that your seat assignment is changed during IROPS. Many FTers recognize that there are certain seats that exist on almost all aircraft and select those seats to minimize disruptions during IROPS.
Another suggestion you post is that BIS MQMs should be treated differently than MQMs earned through credit card or bonuses. There are other threads that expound on the credit card customer having a higher contribution margin than BIS flyers. Delta can’t be all things to all people but IMHO they do a good job of recognizing and rewarding loyalty based on the SM members business with DL. I would counter your position that low fare class GMs and FOs should be restricted from the front cabin. The loyalty and revenue these members provide is a key component of Delta’s success.