Mbynack, please take into account ~224 of the F-15s are F-15E Strike Eagles, aka Mudhens, and they would remain in USAF service due to their lower average airframe ages, along with their ground attack capability, than the air superiority A/B/C/D variants.
Also, take into account that ~120-130 of the Raptors will be in ACC, PACAF, AFRC and ANG units, while the remainder will be for OT&E (422d TES, 411th FTS) and training (43d FS).
F-15E Strike Eagle.
There is a point where numerical superiority can overwhelm technological superiority.
True, in the case of U.S. Army M4 Shermans and Soviet Red Army T-34s exploiting their numerical superiority against the Wehrmacht's advanced Tiger and Panther tanks. Quantity has a quality of its own.
This could repeat itself in the Pacific, where the technologically advanced F-22 Raptors are pitted against the numerically superior Shenyang J-11B Sino-Flankers of the PLAAF.(you know what that stands for)
There is no way that many Raptors is going to win air superiority, let along air dominance in two, maybe three theaters of war. A high-tech war for air superiority against a numerically superior adversary, the last thing a USAF squadron or wing commander or general would have to face, but no choice but to fight.
Why am I excluding the legacy F-15 Eagles? They may be the best 4th Gen fighter to ever roam the skies at will with the crown of best air superiority fighter, but now, the Eagle has handed the crown to her 5th Generation successor, the Raptor.