So, this first is something fairly simple, but useful, and the second a bit more specialized.
I want Aperture smart albums to have the power of iTunes. NOTHING compares to iTunes Smart Albums. In iTunes you have the ability to click an seemingly-untimilited number of '…' buttons which allow you to create a subset of controls to select “Any” or “All” of the following subsets, which work in addition to you main smart album setting of any or all of the following conditions.
Let's say you want an album of ALL of your images shot at the widest aperture on each lens. I don't think you could easily do this right now, but here's how you could do it with this system.
Math ANY of the following
[Group A] - Match ALL of the following: Lens Model XXX, Aperture XX
[Group B] - Match ALL of the following: Lens Model XXX, Aperture XX
[Group C] - Match ALL of the following: Lens Model XXX, Aperture XX
[Group D] - Match ALL of the following: Lens Model XXX, Aperture XX
-etc. Under this system the possibilities are almost limitless. If my description isn't very clear, take a look at iTunes and you'll see what I mean.
The second is a bit more obscure. I'd like Aperture slideshows be able to read LiveType files. Essentially, LiveType is a titling program with Final Cut Pro and Express. It creates titles which you can do any number of effects and build-ins and outs to, and of course customize color, font, etc. all you want. I'd like Aperture to adopt the same interface it does for music files, but to show LiveType files in the same space. So if you have a main background track, you could drag a LiveType file over the photos and it would all the transition and put the marker below the photos. Maybe this time in blue instead of green. I think the ability for nice titles which can be animated would add a lot to slideshows. :) Obviously, it's up to Apple for how they would provide the LiveType app to non-FinalCut users, but I think with the Mac App Store, it's be a reasonable add on for not too much money.