I really think they should look at the max daamge dice of the modifeid spell to figure out the +level needed for the metafeat.
+3 means if you put it on a 4th level spell it would now be a 7th level spell with an expected daamge cap of 10d6 for an area of effect spell. What's the damage cap of a 7th level area of effect spell supposed to be 20d6.
Same thing with the damage function of chain spell at +3 levels its damage cap is signifigantly lower than the damage cap of the level of spell it will be.
Almsot all the metafeats past the originals are screwed up in my opinion, and some of the originals are crap too.(quicken)