A bit heavy for rune-magic, isn't it?
This scale of effect was traditionaly reserved for Divine and Sorcery magic in previous versons of RQ. Spirit Magic (the predecessor of Rune Magic) was very easy to learn compared to these, and was limited. For example Bladesharp was limited to 4 points maximum (+20% attack and +4 damage for 4 Magic Points cost).
Spirit Magic tended to provide marginal but useful enhancements to existing attack modes (Bladesharp, Fire Arrow, Fire Blade, Bludgeon, etc), or relatively weak direct magical atacks - Disruption was realy the only one and it did a flat 1D3 damage.
Rune Magic is a bit harder to learn and use than Spirit Magic was, so perhaps it's reasonable to loosen the restrictions a little but I'd be very cautious about the extent to which I'd recommend that.
One of the main limiting factors for Spirit Magic was that you could only know as many points of Spirit Magic, in total, as your INT. Magic Items that could be used to store extra points of spells were uncommon and very hard and expensive to make. The whole dynamic of this may change with MRQ.
It's very difficult at this stage to estimate how diferent the play ballance will be in MRQ. We'll know more when the Companion comes out.