Is there any more info on your grow? It's very Plant and situation specific so a little trim, or a basic bit of nip and tuck, can work wonders. Especially in a fast-growing scenario (see super-cropping etc).
A very personal thing though. A little trim is best to start off with- but remember alot of 'small' trims in a row are very damaging. A big, healthy plant will have no problems; it's just a fine line indeed.
If you've noted some flower-sites that have potential but are being restricted then take a little but careful to leave big Sun-leaves and structures as good as poss. Don't feel every flower needs light... focus on your tops.
I've had to trim and train plants merely due to lack of space before... if i can only fit, say 5 pots then 2-4 big colas per plant is better than one!
Good luck