Fanaelialae
Legend
One possible approach, if you want to maintain a strong role-oriented game, would be to group each class by role and assign them one or more source keywords.
Limit out-of-role choices to some ratio (say 1 non-role power for every 2 role powers you have). Then source keywords act as hard limits (without a multiclass feat a Wizard can't take martial powers).
Take, for example, the aforementioned Wizard (controller role, arcane source) with a Fighter multiclass feat (martial source). Let's say he has 6 powers total. He could select any powers from the arcane controller and martial controller lists. He could alternately select up to 2 non-controller powers from the arcane and martial lists.
It would detach secondary role from class, allowing players to customize their characters while maintaining strong role separation. You could play a Wizard controller who's a secondary striker, leader, or even defender (or some mix thereof). Or even just focus purely on control.
The downside is that the more buckets you allow players to dip in, the more chances they'll discover unintended (broken) synergies. However, I think you have to accept that as a reality with this kind of approach.
Limit out-of-role choices to some ratio (say 1 non-role power for every 2 role powers you have). Then source keywords act as hard limits (without a multiclass feat a Wizard can't take martial powers).
Take, for example, the aforementioned Wizard (controller role, arcane source) with a Fighter multiclass feat (martial source). Let's say he has 6 powers total. He could select any powers from the arcane controller and martial controller lists. He could alternately select up to 2 non-controller powers from the arcane and martial lists.
It would detach secondary role from class, allowing players to customize their characters while maintaining strong role separation. You could play a Wizard controller who's a secondary striker, leader, or even defender (or some mix thereof). Or even just focus purely on control.
The downside is that the more buckets you allow players to dip in, the more chances they'll discover unintended (broken) synergies. However, I think you have to accept that as a reality with this kind of approach.