Any reason you wouldn’t go with an all electric vehicle at that point?
For example the Ford Fusion Hybrid starts at $25,390 and Prius V at $26,675, the only fully electric vehicle at that price point is the Smart ForTwo electric drive, but the ForTwo Electric has a terrible 58 mile range, only two seats, missing quality of life features, and arguably poor fit & finish (similar to a $13K new car level). A good electric vehicle, like the Bolt, is in the mid $30s ($34-36K ish).
A plug-in hybrid offers a good compromise between features and cost. You'll get similar mileage to a ForTwo Electric (50 miles on electric) but with fewer of the compromises (unlimited gas range after that, more features, nicer finish, four seats, etc).
If I was dictator of everything, and wanted to fight pollution and global warming, I would institute a big carbon tax, and let markets work out how to respond, but my expectation would be that the end state would be plug-in hybrids.
I just looked for long term tests of the Chevy Bolt to see what sort of issues have been appearing on them when driven for a while. Tire failures, battery failures and power steering issues seem to be among them. Of course some of that is under warranty, but also involves leaving the motorist stranded. So maybe focusing on the engine or motor is ignoring the source of most issues.
My 2016 gas-powered Honda has had a few issues, but the one that left me stranded was an electrical issue - the issue with the engine itself did not prevent me from driving to the dealer.
Overall, I think it's pretty rare to have significant work done to a modern gasoline engine - I was recently startled to discover a mechanic I'd been to in the past wouldn't touch my car's engine and referred me to the dealer.
Finally, if you own an all electric vehicle and rent a car for long trips, I'm not sure why that is going to be better than owning a hybrid with a gas engine. You may say the gas engine doesn't have to be hauled around all the time, but then again, the extra batteries don't either, and the rental probably uses more gas and resources per mile than the hybrid running on gas.
As far as overall complexity, a regular hybrid with a modern ECVT transmission (like Ford and Toyota have) is actually a lot simpler than a traditional automatic transmission. Then the plugin version is the same thing but with a bigger battery.
For weight, a plugin-only with 350 mile range would have as much weight as a plugin-hybrid with a 60-100 mile electric range and a low horse power gas engine (the gas would be used to maintain highway speed and trickle charging the battery, and electric used for acceleration).
If you travel frequently by car or can't always count on a charging station being available, then a hybrid could be a better alternative.
The gap is closing, though.