Really it is pointless to compare Gimp and PS, both have their weaknesses and ardent followers.
On the subject of the interface however, I could never understand the 'PS is simpler' when by default there are floating dialogues all over the place. If needed Gimp can be simplified very easily. A comparison of the two
Lots of ways to adjust Gimp, here is one
edit: can't stop the bbs from changing the link so I will have a stab at muxing the url's
The other thing to look at is the use of Activities. The one shown above is for screen capture and has nothing on it except the background and the kicker.
Photivo, worth a try. I found the interface a bit tempremental, the drop down boxes would often close before I could change the settings, might be better now or it might just have been me.
Gimp + Davids Batch Processor ( both in the repo ) might be worth a try as an alternative.
My over-long (12 mins, just watch the first couple of minutes ) take on the subject