It gets a little too into fine mechanical detail but I really agree with your post. In particular:Monster themes: Monsters have a consistent racial power and some monster role powers, enough to be interesting in the combat but easy to apply and track and fit on a single page without reference to spell or class abilities.
Monsters don't require you to flip to other pages which is a result of one of your point below about monsters not being PCs. Having everything in one, simple to consult, place is the best. Having monsters using PC spells is just the worst idea ever.
Totally agree on both. Monsters should be designed with their short life span in mind and with enough variety to make interesting encounters.Monster variations: Most every monster has a few variations across some types and levels.
Monsters are not PCs: Monsters do not follow the same rules as PCs, including different resource management considerations (recharge powers for instance instead of encounter or dailies on a formula).