ElfQuest Magic
A lot of the costs need to be fiddled with, but the basic idea comes across... Was hard balancing the abilities (they're way weaker than anything a spell-caster of equivalent level could do, usually, except they can be done a lot more often) but I think with some play-testing things can be worked out. Should definitely work as a system in an rp-heavy game.
Also implicit to this is using the abilities in non-specified ways... Say you wanted to have a stone-shaper ride a crest of stone over several large jutting rocks in a chasm... There's nothing there that specifically says they can do that (they can shape cubic feet of stone, but what if they want to do it quickly with less precision, sucking the stone back up behind, et cetera...) One option would be to use calculus, another would be to say "that sounds somewhere between Stone Waves and Encase Creature in terms of difficult, so I'll say it requires level 11+, with a cost of 15 per 5 feet moved." The whole system is focused on being as free-form as possible (by combining multiple abilities in one casting, et cetera)
Further, the logic of the system focuses on Wisdom first, Charisma second, and Intelligence last, all though all three effect casters... A run-down:
Wisdom: Effects how much you can cast in a round. Also improves certain magic effects directly.
Charisma: Used for save DCs.
Intelligence: Prereq for meta-magic style feats.
I think this naturally covers all the styles of spell-casting: The wisdom-based caster who uses spells the way they come to them, the charismatic caster whose spell-power is a threatening force, and the meticulous, studied caster who learns to shape their abilities in new ways.
The system naturally favors Wisdom over the other stats, as it seems most important in Elven spell-casting in general. Non-elven spell-casting is another issue, and one not covered here at all(although the PHB Wizard may be appropriate, if you nerf all setting-inappropriate spells.)
Also note that these are
highly specialized classes... More highly specialized than anything in the PHB. Because of this, a single-classed magic-user is going to seem generally weaker in an adventure than the non-magic classes; this is based on the assumption that most elven spell-casters are multi-classed. Unlike the PHB casters, this magic is built to work
well with multi-classing: Its usage does scale independent of the spell-casting class (more hit points results in more spells per day, essentially), without negating the usefulness of advancing in that class (access to more powerful abilities.)
I'd consider an option for the Elven races (excluding Go-Backs) where the highest level spell-casting class is not taken into account for multi-class XP penalties. This allows for Healer/Fighters, Plantshaper/Rangers, et cetera, all within one tribe. This simulates (somewhat) the "in-born talent" nature of elven spell-casting, while still allowing the D&D-style flexibility that lets a character make a Healer/Plantshaper/Telekin if they
really want to.
Oh, and "Telekin" was the best name I could come up with (Telekineticist was too damn long)... "Sender" is also somewhat inaccurate to the Suntop style of magic, but again, best I could come up with. Feel free to change those (and add the flavor text which is sorely lacking from the abilities.)