Regarding the height of the stage I've been to several concerts with pits in:
Jessie J - the beginnings of the sides of the catwalks were a bit too high but the rest of the stage was perfect, you could lean on it!
Taylor Swift - at the front it was fine, the rest of the catwalks were really really low!
Madonna - main stage was quite high so sometimes you didn't see the whole show when at the very front
Lady Gaga - pretty good, not very good outside of the pit as you couldn't see the main stage though!
I think it will be fine but tbh every single position in the pits is perfect, so even if I get the opportunity to be front row I wouldn't necessarily take it as you don't focus on the whole show!