I'm actually an experienced play by post role player. As I grew up in a small town that didn't have a large roleplay community. I actually didn't know D&D was a thing until going to college.
And oddly enough, I had been designing a ruleset for a play by post rpg myself before Covid-19 hit as I find that D&D and pathfinder are not the best for those rules, but I still have a fondness for the old play by post style.
So first let me give you some ideas that will make life easier for a GM running a play by post-game.
First abstract distance: Instead of telling your players how many feet they are from the goblin tell them how many move actions they would have to take in order to get to the goblin. Pathfinder 2nd edition's flexible action system is actually really good for play by post games.
I like what you're doing with initiative as it keeps those rolls relevant without bogging down the game. My solution to this was actually skipping initiative most of the time and letting players take their turns when they had time to. Or even saving actions until they see what the foe was going to do. It doesn't break things as much as you might think.
Next, you need to have a different type of dungeon layout then you do when playing in person. I base my play by post dungeons off those old MUD games that I used to play, back in the day. You should have a clear number of exits, and you should describe them as being, exit to the north, exit to the east, etc...that keeps it easy for players to visualize.
I also find it helpful to divide the game into episodes to keep things moving. If the players travel or the setting changes you can change the episode. This should give you the opportunity to recap in some way. And let me be clear, even if you don't use an episode type structure. Recapping is important. Even though the players should just be able to slide back up the chat to see what happened last, a lot of times they don't and they need to be reminded of what's happening and why they're doing something.
Do away with rules that require action vagueness. Most of the time the RAW state that the players don't know what a spell being cast is unless they can make the relevant skill roll. This doesn't work in a play by post. When an enemy spellcaster casts a spell, write. Goblin sorcerer casts fire ball. Then on a separate line write "These players need to make a reflex save."
I hope that helps, honestly, I find that while Pathfinder 2nd is an okay game to do a play by post game with. The complex network of skills and feats that make up the character sheet makes it much harder to keep track of who can do what. And players tend to forget their options quite a bit. That for me was always the hardest problem to solve.
Good luck, and stay safe.