The biggest fixable issue is the whole thing where all electoral votes in most states go to one candidate. That is a thing that is fixable. Because that is a matter of state law. The problem being of course that most states don't want to change that, because for most states it would mean less attention from presidential candidates because they'd be playing less of a role in determining who wins (by being worth a smaller, harder to shift margin). Convince every state to switch to the way Maine and Nebraska hand out electoral votes (2 based on statewide popular vote, one for each house districts vote - states get one elector for each member of Congress this assigns electors based on who would vote for that member of Congress) and the problem is mostly fixed (everything except not being able to win the presidency by just winning California and New York by large enough margins and having an average showing elsewhere). Importantly, it's fixed in a way you don't have to get most of the states to agree with all at once to make happen.

Abolishing the electoral college outright would require a constitutional amendment and those are intentionally very hard to do. An interstate compact to functionally eliminate it by getting 270 electoral votes worth of states to agree to assign their electors based on the national popular vote rather than anything at the state level is somewhat more doable but will also be legally challenged under the doctrine that the federal government is supposed to approve any interstate compact.

Several states have even proposed banning him from the ballot for his coup attempt, including mine. Unfortunately they are being tossed out, probably by judges that he put in power.

Any judge that gives a fuck about the law and the Constitution is going to toss those out, as they are premature. He's a fuckwit that's awful in all kinds of ways, but he is still due due process. Arguing 14th Amendment Section 3 applies to Trump requires arguing he has engaged in insurrection or rebellion or given aid or comfort to an enemy. Which he probably did, but "probably" is not generally a standard we punish or restrict people over, nor do we do that without due process and the only process so far in this case is "has been investigated and formally accused".

This is one of the reasons that the Trump legal teams first and highest goal is to delay. If they delay long enough they can argue that the courts are being used as a form of electoral interference and possibly give Trump an election boost, if they delay even longer and he wins they can argue executive immunity. Because that's the path with the best odds for Trump - he's much better at manipulating crowds than at lying to judges.