I can definitely see the need to mess with the system for play by post games. Torchbearer is one of my favorite systems and I play it rules as written at the table. However, I have a group of friends spread over the country and we use facebook for play by post gaming. However, I use Dungeon Crawl Classics, with a couple rules changes for that, and it works pretty well. I can’t see normal Torchbearer ever working in that format. So, I think you’re definitely on to something for that form of play.
If I were running it, I would keep checks and explain the checks mechanic - you need one to get into camp and do stuff. I think the traits mechanic hinges on it. I also don’t understand the change from skills to talents and tactics. I would just leave it as skills and have the regular pass/fail advancement for those. Lastly, I would personally prefer to keep classes and levels in, just because I enjoy that kind of advancement, although it would require some fiddling when it comes to the level up powers due to all your changes. In which case, you could keep Persona in the game. Persona allows you to spend one point to get +1D ahead of the roll, which works fine for play by post. You could award it during town phases to make up for no end of session stuff. This would also allow you to keep Belief, Instinct, and Goals, all of which I think are very important to the game. It would also allow you to track the amount of Persona spent and level up, using a rough gauge based on the normal game.
This is your game, though, so it’s a very subjective thing when you’re picking the mechanics out of Torchbearer that you like the most, doing your best not to break the game. But, the important thing is that you and your players are having fun. If you’re having fun, you’re doing it right.