In my book, a deal's a deal. When States join the Union on the basis of contractual obligations and promises, if we then change the rules we should let States go free.
We would be better off if we let the States select the Senators as they wish, and hopefully held them accountable for representing the States' interest. As it is now, the States are disenfranchised in this system.
The idea of abolishing the Electoral College would further downgrade the "Constitutional Republic" form of government we once had, which was supposed to give small states and regional interests some clout, antidotal to the evils of democracy such as "mob rule" , "majority tyranny", and complete degeneration of individual rights. The design of the government at the outset was intended to discourage special interests, individuals with inordinate lust for power, and intolerant majority slices of the population from being able to deny individuals or States their inherent rights. States are not super-counties, they are, or should be, sovereign governmental entities with defined powers, actually separate powers from those delegated to the Federal government.
If we continue to downgrade the separation of powers, or the powers held by States, or the rights held by individuals, we are vulnerable to tyranny, possibly mob rule.