I've done similar tire changes in the past (up 1 size basically) and for me it meant:
1) slightly more sluggish acceleration- noticeable, but not particular bothersome to me
2) a slightly better ride (more sidewall) assuming same tread aggressiveness
3) a small loss in steering sharpness (a touch more 'wander' due to wider tread)
4) a bit more ground clearance & a higher step-in
5) only a slight drop in MPG, if any...more-or-less a wash
Above based on going from 275/70s to 285/75s on a 2002 Land Cruiser, going from 225/70s to 235/75s on a 1990 Cherokee, and downsizing from 285/75s to 265/75s on a 2002 F250 7.3L.
To state the obvious going up more than 1 size will make the above more pronounced.