Before you flame me, bear in mind that I have two sorcerers that are my main characters and are my favorite class to play. I've played this game long enough to know that a change like this will have some consequences that weren't thought out very well.
1. Sorcerers cannot swap spells at will (tavern, shrine or otherwise). And take considerable amount of time to swap a number of spells in and out.
2. Sorcerers are feat and AP starved.
3. The damage gained does not outweigh the heavy loss in versatility (and sorcerers are not very versatile to begin with).
So, you are in fact forcing players to either TRing or LRing at the very least just so that we can take advantage of any one given line of focus. You are also creating an environment where certain builds will be heavily favored and all other builds heavily segregated against. Who would ever want a fire Savant for any of the Devil story line, for instance. Or a Cold Savant for necro quests? So, some people (myself included) won't use the PrEs at all. Don't want to spend $8 (or so) on an LR heart nor do I have the desire to TR so that I can get those extra two points to STR and go with a PrE then then having to LR into a different PrE because of level and quest type demand different kinds of damage. None of the other PrEs for any class requires builds to be LRd. Most of them can be fixed with couple feat swaps (which could be acceptable for sorcerers too). But fighter Kensai, for intance, if they go full focus on, say, Scimis, doesn't mean that they will have a 30% DPS penalty on Long Swords and their BaB lowered to 17, for instance.
For these reasons, I'd like Devs to reconsider the sorcerer PrE Savant lines. I would rather wait until a patch after Update 9 than having a broken, IMO, PrE line just for the sake of having them.