Those icons are generally the most intuitive and distinguishable so far, for the vf the one with the big and small wheel is best. Except for the two arrow symbols, those will be easily mixed up. This could be solved by just not displaying engineer tools on the minimap, as they aren't buildings anyway.
Radar can easily look more like a radar dish, even at that scale. You could probably make an eye for the camera as well. Mspaint > photoshop
I recognized the Combine and Marathon logos in Dizzy's old icons. There's probably a couple more; the refinery, vf and armory logos look vaguely familiar. Dizzy's revised icons are much better, and they're more recognizeable than dogetti's. Though, given the current vehicle icons, I figured the building icons would be silhouette-based as well.
I don't really like how -dishes like that- look, in general. I made some small changes from the feedback: I like the first radar icon the most myself, as it's beefy and simple, but I tried to make some that looked more radars, without looking like a cup with a pointy stick. Gave the vf cog bigger teeth. Tried to make the armory icon look smaller Added a crosshair looking turret icon, while again trying to make it look less beefy than the primary structures. Tried a couple of small cameras, but the satellite looking contraption I liked the most because it's not as beefy as the primary structures and I guess looks like something uplinkish, I dno, I'm just anal about having primary structures be a bit more beefy overall, I would prefer armory and repair station be slightly smaller than the rest and turret and engi radar/cam to be even smaller. When I have some more time I'll fix up the armory icon, don't really like the way it looks, but I'll just make it a bullet. Don't be fooled by the dark blue background of this forum, the last turret icon has a black crosshair.
One thing to keep in mind; if you absolutely hate an icon set, you can always replace it yourself after release. After taking that in into account, I would have to shift my vote from set 1 to set 3.
i know these are no match for the other 3 sets, but i was bored i even added some things that normally don't make it on the minimap (everything is made in flash with vectors) in order from left up to right down corpse (dead player) radar/camera thingy landmine player jeep apc light tank/medium tank heavy tank artillery command vehicle machine gun turret rocket turret commander vision repair pad vehicle factory radar refinery barracks armory
what ever is decided, I want charicter arrows smaller. I would love if all icons were scaled to match the size of the structure.
I kind of liked your original #3 icons (the ones to the left) the best. The more detailed icons (like the newer ones for the radar and engy cam/radar) are harder to distinguish with a quick glance.
Imagine if your playing com and you tap "I" and it toggles all these icons above the buildings in the view screen along with respective icons over units identifying class.
#3 by far is my choice, since the majority of the icons are highly intuitive, as opposed to mostly abstract for the other sets. I'm not sure what the extra two icons for the VF are. Alternate icons I suppose? I'd probably pick the 1st alternate over the primary, to make it more distinct from the Armory. I also like Zeke's suggestion for altering the icon for the turret, to look more like a turret. EDIT: didn't realize dizzy posted a revision of his revision in the pages. I still stand by my vote, but I reject the alternates for the radar, and the engy turret and radar. They're way too complex, and wouldn't be any more useful if the map got even a bit crowded. I'd pick the last VF alternate over the primary, but still like the first alternate most. I also like the Armory's alternate more than the primary. I reject Repair Pad alternate, since it is now bigger than the original icon. If the Alternate Armory icon is used, the alternate R.P. icon should be used as well, to keep them distinct from each other. If another Alternate icon for the Armory is made, use the original R.P. icon.