Hello Mrshmello,
1) No photoshop in Chrome OS afaik - but there are alternatives -
here and
here
There is also the excellent 3D Sketchup.
....which Eclipse are you after? ...
this,
this or
this?
Looks like you may be out of luck.
2) Yup, USB 2 and 3 on this Acer C720, both work with HDDs and USB sticks.
3)
Oy veh iz mir, I don't know for sure.....
Good luck!