VCC pour and decoupling capacitors on a dual layer board
There are pros and cons.

The advantage of ground on both sides is that you can tie the two ground planes together directly with vias. The advantage ofone side power and the other side ground is that it can provide lower DC voltage drop.

Whatever you do for high speed signals you need to think about your high frequency return paths. The return path should generally be as close as possible to the signal path to minimise inductance. If part of the return path flows through a power plane and part through a ground plane you can tie them together with a capacitor.

A 2 layer board will always be a compromise for high speed because your planes inevitablly end up quite "cut up". 

As far as providing power decoupling for the ICs themselves the general rule is that it should be as close to the IC as practical. Your board seems to have a lot of unnessacery space between the capacitors and the IC.