I entered 7 generations of one family (575 typed pages) by hand, it took me 18 months. I didn't have a GEDCOM to upload. it can be done.
On the other hand. you're relatively new to WikiTree, take the time to enter the first (oldest) 100 or 200 profiles. Then import a very small sample, no more that 50 in a GEDCOM and see how much editing they need (you will have learned the tricks by then. )
Then you can decide which is more effective.