there are less lethal rounds such as beanbags and rubber balls.
I do detest the term "less lethal", because it simply is not true. I realize it is short for "less LIKELY to be lethal" but it gives the impression those crowd control rounds are "less lethal" /"less than lethal", etc., and that simply isn't the case. If one of those beanbag or rubber balls hits you in the right spot, it WILL kill you dead as a stone. The reason they are less likely to be lethal is because they aren't supposed to be shot directly AT people.
Round nose (yes, that's "ball")
round nose doesn't make it "ball" ammo. Ball can be round nose, or it can be spitzer, or almost any design in between. In the days of flintlocks, ball was just that, a single round (lead) ball (of roughly bore diameter). called "Ball" because that's what it was, and to distinguish it from shot (several smaller balls). Since it was the standard military ammo the term ball was just carried through as technology changed the projectiles from balls to bullets. Minnie Ball, was hollow base lead bullet. Single projectiles stayed "ball ammo" even when they became full metal jacketed bullets of different shapes. Today, its still "ball" ammo, meaning its JUST a standard bullet, and not anything else (such as tracer, etc.)
what other kinds of rounds are there? You hit all the major ones I can think of, except for Dummy rounds. and Line Throwing rounds (which are not exactly the same as blanks).
There have been commercial sabot rounds that were never meant to be SLAP rounds. Remington Accelerators are/were sabot rounds but armor piercing was never their purpose.
oh, almost forgot, there are Training Rounds, which are NOT blanks. Not sure about other countries, but the West Germans used them in their 7,62MM NATO H&K rifles. The cases are plastic, with a brass base, and molded in bullet. When fired the bullet tears off and does go downrange at considerable speed (something like 5000+fps) However, being plastic and weighing something like 17gr (if I remember right) it loses velocity VERY rapidly. Possibly lethal point blank, but at 50+ yds, it's supposed to just sting...a lot!
There's probably other rare or specialty types, but I can't think of them right now..