I used plastic snap-together tiles from costco on the main part of my floor and they look fine. They've been in about 7 years now. There's a small step up to a landing before the door to the house where I used epoxy from home depot. I think it was Rustoleum. It still looks fine, although it's picked up some stains that haven't come out with some casual mopping. One thing I noticed is the concrete cracked slightly and obviously that shows clearly through the epoxy. If the concrete cracks under the tiles it doesn't show.

I just finished mine last week. I used interlocking tiles for the main floor, and epoxy for the upper landing area. You might want to get a few more quotes, as $5/ft for the epoxy sounds on the high side. I've seen it advertised at Home Depot for about $2.50/ft. You're correct that spills can get between the tiles. That's definitely a downside, but I view the tiles as essentially permanent. The next owner of my house can worry about it if they want to take the tiles out. You could also do a vapor barrier if you're really concerned - something simple like heavy plastic sheeting would do the trick. Here's a couple photos.

None of the DIY stuff hold up that well. Your garage mat can pull it off. Do a garage mat or paint. Not both.

I have a "chip" floor in the basement and a quartz aggregate floor in the garage. Both commercial. The "chip" floor was done by prepping the floor, putting down a layer of "sticky stuff", and then dumping several boxes of chips on the floor and raking them all around to fully embed. My floor is "solid" chips - not sprinkled on like shown and available in the DIY kits. The chips are about 1/16" thick and then they used a blower to blow off any stragglers. Then - several costs of clear epoxy were applied, still leaving a slight texture for slip resistance. The quartz aggregate floor is troweled on to whatever thickness is necessary, can be used to repair cracks / smooth. It also can be used to cove up the wall and fill in the corner condition where expansion strips were used and sometimes leave an ugly corner that just collects crap. We troweled this up the wall to meet the trim on top of the foundation / transition to sheetrock. I don't think we could get either result with a DIY product or process.