a nice discussion really
overall I don't count odds delay as an abuse but I try to avoid them as much as I can just because most likely my account will be super limited by taking such bets
at the end all sportsbetting sites have rules and they can void the bets whenever they want so sometimes books can be  unfair with their customers as well
also if we count this as an abuse then arbitrage may be considered the same as well , for me both are fine and as I said the books can always use their void sword so bettors aren't breaking any rules

the 2nd and 3rd ones are abuses and should be reported , never seen the 2nd one happening tho

the trading one is normal , the other traders aren't responsible for others' mistakes and they may be using bots as well
overall I can't see how this can happen , even if you put small orders the exchange should be matching you with the highest buy orders
unless you are doing it with a small coin and that can be explained as a try to dump the market and get rid of that coin