If you find Sydney annoying, then the comic is very clearly NOT for you.
That's the conclusion I came to. To each their own so I'm not gonna write a lot of words about stuff I did not like (I'm tempted sometimes, but usually think better of it) but I did give Grrl Power a try and after a few chapters (including skipping ahead a bit since often webcomics have a rough beginning and get better later) there was no escaping that I did not like the art style, I did not like the setting, I did not like the writing, and I did not like the main characters (not just Sydney -- I also dislike Max, Dabbler, Harem, etc.).
I actually like finished comics, I recommend miracle of science as a fun but somewhat obscure one (it is not a particularly serious comic but I enjoyed it).
Most of my favorites can be easily found. So I'll only mention 2 comics that I found with some difficulty.
Found the first by accident. Not in any list afaik.
Stonebreaker https://stonebreakercomic.com/ Fantasy / Ancient civilization / 'Demons' vs Humans
This one is rank 590 in Topwebcomics. Imho it deserves a higher spot.
Hominids http://hominidscomic.com/ Neanderthalensis vs Sapiens / fantasy / 1 alien / stopped updating