You don't see anybody answering regarding the "A" in 204 for the same reason it was discontinued, it isn't/wasn't very popular and they didn't sell very many. The only guys I actually know that bought the "A" after it was discontinued and blown out by the wholesalers were collectors that bought one for their collections and more for trade stock later down the road when they become scarce.
I could have purchased an "A" for exactly what I paid for my "AB from the same seller but it made ZERO sense to have it in a 22" barreled rifle WITH sights that were never going to be used and that were going have to be accomodated for whatever scope was going on it.
Hence for a walk around shooter the "AB" sans sights made a lot more sense. You give up a few 100 fps over the "B" or the "V" with their 26" barrels but you are still driving a 35grainer at 3600+ fps.
I'm not sure ricochete is an issue that any of us worried about when we bought our 204s. Lots of things out there with light frangible bullets serve that purpose just fine.
The advantage to the 17 center fires and the 204 is SPEED and ZERO recoil. You can see your bullets hit hence you don;t need a spotter. That said it and the other smaller caliber light bullet cartridges are very very specialized and in reality are 250 yard rounds and on in. MUCH past that and they have shed enough velocity that energy is WAY. The BC is low enough that once they shed that velocity drift becomes a very serious issue.
Years ago I shot the rifle course course with my #1 "B" is 17 Remington with 30 grain Bergers driven at 4000 fps.
It would blow a hole right through the chickens and knock them back 2 feet. If you hit the javelina in the top inch of the back it would fall off the rail, slowly. If you managed to hit the turkey within 1/4" of the top of the head, it would turn SLOWLY and slide off the rail, MOST of the time. I don't remember ever hitting the ram.
The small calibers, 14s, 17s, 19s and 20s are NOT long range varmint cartridges and I not consider any of them as coyote rifle much past 200 yards.
By the way once you go past the 35 grainers in the 204, recoil actually starts to become an issue and the heavier for caliber bullets WILL carry your eye off target with any scope over about 10x or so. Like I said the niche in which it fits is VERY narrow.
I personally don't consider it a good all around varmint cartridge and would never recommend it to the beginer/novice.
Ross