>>1889197I've circled in red some of the spots that are inconsistent or just too thin/bold and in green where the thickness is just right. Rule of thumb is to keep your nodes in pairs (which you seem to have been doing already) and make their handles parallel to each other.
I would also personally recommend that you pass on to a new project and not dwell on this one and try to get it perfect for too long since it is only your first attempt. It'll take a lot more practice before your get the gist of it. And again, for a first attempt, it's fairly good.