The other party needs to run better candidates. It’s their job to drive voter turnout in their favor (not internet argument warriors) and they’ve lost two out of the last three elections by sabotaging their own primaries and doing “Our candidate isn’t good but at least they’re not a got dang cheeto!!” campaigns.
“Less bad doesn’t have to mean good” is a mantra with a current 67% loss rate, soon to be 75%, and then 80% four years after that if they keep trying it. And they’ll keep blaming the voters that they failed every time.
There also needs to be, probably, more party diversity.
The fact that the current president has such a stranglehold over their party is pretty unprecedented; normally, the big tent parties have lots of little camps with power bases that somewhat insulate independence, whether that be on an issue or regional level. It's kind of odd that the disenfranchised members of that party have not started up their own party.
Also, I think the current gerrymandering race to the bottom has pretty clearly demonstrated the need for a better system of voting and district mapping. The House elections are already regulated by congressional act, not by the constitution.