This is exciting to me! My main piece of advice for you (if you are in the mood for advice) is to not let whether you end up finishing your OS or not be the measure of your success. As others have said, you've embarked on a very ambitious project, but even if you don't end up finishing, you're going to have learned a lot of pretty amazing stuff. So just try to enter into it with that frame of mind: even if your OS doesn't work out great, it's still probably been a success.
One of the reasons I loved hacking so much was because in order to do it successfully, I had to really get into the mind of pixel, how he liked to make things, and why. When I wanted to find something, or figure out how something worked, it was mostly a process of imagining myself a pixel, and seeing what he would do. This sort of hacker's empathy was why I liked to change things more than make up new ones, but its also, I think, why so many people have a much harder time with reverse-engineering and with hacking than they do with engineering and creating. That is to say, your previous struggles with assembly may have more to do with the context you were using it in than the language itself.
Lastly, I hope you have a deep love of the fundamental, nitty-gritty, low-level stuff, because otherwise this project's going to make you an unhappy soul. It can certainly be frustrating when you're coding x86 and just wish you could use printf, or HashMaps, or the map function, but it's also what makes it such a fun and rewarding thing to do -- you get to see what almost nobody else ever does: what makes a computer tick