Nothing against to your procedure with manual set,
but then good luck with some quite long flight to fill FPL. As I said some time before, I simply curious how many bad FPLs are available in Simbrief as data bank. Looks like people don’t care what is really inside and then this is problem. Really I don’t use Simbrief due that bad/wrong FPLs repository, best is do FPLs by yourself, another good planner with save option to msfs type is required. If you want use Simbrief, ok but you need then do some corrections as you mentioned.