I have had other requests for "my" route out of Reading. It may not be the best way (and certainly is not the shortest) but it is reasonably pleasant and not to much traffic. To be honest, the A33/M4 interchange shouldn't be too much problem at that time on a Saturday morning
Out of station by main entrance.
L and immediately 2nd exit RBT (ignoring bus layby)
along Station Road (Malmaison Hotel on L)
SA at Traffic lights into pedestrianised Q Victoria St
R @ T (opp John Lewis) still pedestrianised
SA at mini RBT onto proper road (Oxford Road)
After blue railway bridge, 1st L Western Elms Avenue
at top (that is a clue to the topography!) of W Elms, R@T, imm L (Southcote Road)
at end of Southcote Rd dismount and cross A4 Bath Road
1st exit RBT (Southcote Lane)
SA a couple of RBts to
L @ T (maybe traffic lights) Burghfield Road
over river and canal (traffic lights)
Imm after M4 bridge, L
after c 1 km R sp Grazeley (you are on final part of KVR route now)
R @ T, and 1st R into Arrivee
The route can be reversed for the return to Reading (without the need to dismount to cross Bath Road!) without "one way" problems.