So East Coast is the way to go, but you have to make it as far west as Ohio. If you can afford it you can add on a weekend in Los Angeles just to do the other Disney Parks & SFMM.
Here's my list (north to south):
Canada's Wonderland
SFNE (for Bizarro) & Lake Compounce (for Boulder Dash)
Waldameer (for Ravine Flyer II) & Kennywood
SFGAdv
CP
SFGAm
Hersheypark
Knoebels
KI
Holiday World
BGE
SFOG
There are huge gaps between some of these parks that could be filled by King's Dominion, Carowinds, Dollywood, SFKK, Indiana Beach & Darien Lake (to name a few). Knoebels doesn't require a whole day, so I would do Dorney Park that morning.
There are some other parks to squeeze in there, but it's a killer trip as is - both monetarily & time/distance wise.
SFNE/LC to SFGAdv to DP/Knoebels to Hershey to Kennywood/Waldy to CP to KI to HW to IB to SFGAm is a good trip, but it leaves out BGE, SFoG & CW. It also requires flying into Boston & departing from Chicago.
SFNE/LC to SFGAdv to KD to BGE to Carowinds to SFoG to Dollywood to HW to KI to CP to Kennywood/Waldy to Dl to CW is another, but then you leave out Hershey, DP/Knoebels & SFGAm. This one is fly into Boston & depart from Toronto.
CW to DL/Waldy to CP to KI to HW to Dollywood to SFoG to Carowinds to BGE to KD to SFGAdv to SFNE/LC to DP/Knoebels to Hershey to Kennywood only leaves out SFGAm. Here you fly into Toronto & depart from Pittsburgh.
There are so many possibilities, it really depends on which parks are a must for you & which must parks are you willing to give up.
For me it's CP, SFGAdv, BGE, SFNE/LC, Hershey & KI. You can fit Knoebels/DP, Kennywood/Waldy, KD & HW into this grouping. CW, SFoG & SFGAm are all too far out of the way, but any one can be added on without too much of a problem. BGE is as well, but is too good to pass up.
So how deep are your pockets & how much time can you spare?