I'm not opposed to the measure but it would only work nationally with an independent redistricting that didn't take into account any partisan metrics, including competitiveness/balance.
Even an independent redistricting commission doesn't always lead to proportional results, as you should know based on your avatar.
Short of abolishing (or effectively abolishing via NPVIC) the electoral college, the next-best solution would be to require all electoral votes to be allocated proportionally. This would actually get rid of the main problem with the electoral college and make a split much less likely. It wouldn't solve the "Wyoming is more represented than California" problem, but that's less of an issue than people think, because Wyoming doesn't have that many electoral votes in total. It will probably never happen though, because no state is going to unilaterally disarm by giving a big chunk of their electoral votes to the opposing party, and in cases where the state legislators
are the opposing party (e.g. New Hampshire, arguably Georgia) they're more likely to go the Maine route, and even then it's risky because their party could still win the state outright.
As for the New Hampshire proposal, I oppose stuff like this on principle, although in small states like Maine, New Hampshire, and Nebraska, it's not as bad as it could be elsewhere.