like you i'm leery of combination contraptions. Even in my electronics, I like components. I've have an old mini here on loan that i'm enjoying. My needs are small compared to others so a new mini will suit my purposes and I can select a monitor, keyboard and mouse of my choosing. Simple, small, cool with options, it's hard to beat. 
if you need service dragging a mini to an apple store seems more appealing.
We're getting rid of most of our iMAC G5's this calendar year and while there is one out of the 83 or so we have that has been really problematic (two bouts of p/s and or logic board replacements, seven G5's that have had something replaced in warranty) they are all out of even the extended warranty now so I'm reluctant to get on Apple about further replacement beyond extended warranty! I just hope the 20" iMAC Intels prove to be a less problematic design; although their habit of low balling the power supply purchase is probably still happening. If I can't afford a tower (and I can't) I guess I still would go with a Mac Mini just because there is less to go wrong when you take the LCD circuitry out of the mix.