I gave Grand Master Trainings something i called Regimen they had to do.. it takes and indeterminate amount of time but the idea was that if you quit doing the regimen the skill would fade and was theoretically being replaced by some other regimen...
Its an interesting idea, though in essence it is basically the 4e "swap out a power/feat/etc at each level" but maybe a bit more flexible.
Anyway, all of these verge on something pretty much like good old Vancian, you pick which tricks you want to know today, spend some time 'memorizing' them (which can be fluffed in all sorts of ways) and that's your day's options.
So, maybe here are some interesting alternatives, or tweaks. You could perform one of these rituals at any time, and the effects are permanent. That is once you cast ritual X and thus select power N, you have it until you reuse that slot for something else (this implies there are a limited number of slots). Each ritual has a casting cost in Vitality Points (or whatever, HS if you will), and some casting time (say one minute, but maybe some are longer). Thus you don't really want to be changing too often, but its perfectly feasible to have a few 'contingency' options. You could also invoke a power by casting the ritual instantly, so if you suddenly need the 'Remove Curse' power, then you can just cast the ritual on the spot, its slower, but for things you won't use too often, or that have relatively little utility within an 'action sequence' (combat or similar) its a good option.
This also allows for a system where you can avoid forcing people to choose combat options. You can learn any numbers of rituals (practices use the same rules I'm assuming) but you won't have to actually put the powers in slots unless they actually help you in a fight. So, you will be limited to a certain number of combat options, but other options can be picked up (albeit maybe they are slower to use if you don't slot them) and utilized without competing with those.
Now, it will be up to the GM to be reasonable in limiting access to rituals, otherwise characters could have pretty much every non-combat capability known to man, elf, or dwarf, but its no more an issue than any kind of treasure/item, and they can be accounted using the same mechanical limiters (IE an item is really no different from a ritual in practical effect, you just 'activate it' instead of 'performing' it, and I guess it can be taken away, but if you have foci or ritual components then all these things are pretty much equal).
