A simple change that I think would make roads a bit more friendly for combat, without making it "safe"
When you teleport, you have 5 seconds on arrival in which you're immune to any attacks, but you can still be aggro'd.
This makes it so that if you get ambushed, there's a chance for the screen to load, but NOT a chance for you to just 'hearth away' before anyone can attack.
A simple (I presume) status would do the trick.
No one gets away safe, they're still grounded with the aggro No-Hearth, but nor do the ambushers get an unfair advantage by attacking during screen load.
Any problems with this?