The F-35 is unrealistic only because of price and US objections. It's definitely not cheap, but it is indeed seen as the "F-16" of the next generation, whereas the F-22 is more like the F-15. In of itself, the fighter is actually a good fit for Taiwan, assuming the weather isn't an issue. In particular, the ability for vertical or shortened takeoffs on smaller runways would be critical in response to a mass first-wave attack, given that it's likely that most of the major runways would be heavily damaged by ballistic missiles. Previously the only option would have been the AV-8B, which was notoriously difficult to operate and thus not worth the trouble.
The ROC's recently released quadrennial military review was interesting in that it ran counter to previous China-friendly drafts. The harder line is perhaps a criticism of the administration for giving up too much to China without getting anything in return. It seems like Ma has focused on fighting back against a ground assault, rather than contest the skies first. Again, it's possible that the administration is sort of writing off air defense because of the likelihood of runways getting destroyed, which again emphasizes the desire for F-35s. Doesn't hurt to ask - at the very least, politically the ball is shifted towards the United States for denying a sale, weakening criticism asserting that Taiwan is not serious about defense.
Seems like an interesting situation of the military holding different views of the government.