I'm right with Olivier on one point: whatever set of parameters makes you feel best, go with them, but don't expect them to be the same set of parameters that the HP Club accepts. But as for me, it sounds like your take on things is awfully man-oriented, and not very geological or geographical. Of course, the state boundaries are manmade political boundaries, so no one doing state ANYthings escapes this critique entirely. But to me, the crux of highpointing is ascending what's naturally the highpoint. I'm not in this for cities or structures. I'm in it to hike and climb. (Which is why i adopt my own self-power hiking parameters.)
As for IL, using the reason that it's inconvenient to abide by the Wuebbel's rules doesn't sit with me. Highpointing is all about inconveniences. Having to adapt to Wuebbel Season is no less convenient than trying to capture a slim weather window on Denali. The "ugliness" reason for not doing the Mound doesn't sit well with me either. If you're after summit aesthetics, skip highpointing altogether and spend the equivalent time climbing mountains in the Wind Rivers or someplace. The beauty of highpointing, as expressed over and over on here by so many people, is in the variety and the unexpected. I think there's good reason to have some mounds, pastures, and trailers to visit, along with soaring peaks. It gives one the true cross-section of what it's like in 50 states.
I suppose adding manmade structures to your accepted list still gives one a cross-section, albeit an unnatural one. Go for it. You may be the first to complete them! Just one more thought though:
Not climbing the antennae needle on the Sears Tower = Not crossing the crater to Rainier's true summit.
p.s. Daniel, email or call the Wuebbels and ask them. I talked to them a few years ago just after the rules were announced but a few weeks after i already had my travel plans set, and they were reasonable about letting me visit on an offdate. I know they said "no" to other requests after mine (maybe they got sick of being asked), but it seems if you gave them several years notice of what you were doing that they would accomodate you.