These tips are really important and you did a great job in pointing out the criteria which everyone can bear in mind before choosing the most appropriate broker.
As for me, apart from regulation, which is very important, I also look at the overall opinion of trading community. I believe that it is one of the best ways to know whether a broker is worth consideration, is to ask the traders who actually trade with this broker. More than that, if I were a scalper or an algotrader, I would also be curious about whether this broker allows scalpers to trade and whether it allows EAs or any other trading bots. There are many brokers who prohibit scalpers to open positions for less than a minute. This can have a dramatic effects on trading results.
As for me, apart from regulation, which is very important, I also look at the overall opinion of trading community. I believe that it is one of the best ways to know whether a broker is worth consideration, is to ask the traders who actually trade with this broker. More than that, if I were a scalper or an algotrader, I would also be curious about whether this broker allows scalpers to trade and whether it allows EAs or any other trading bots. There are many brokers who prohibit scalpers to open positions for less than a minute. This can have a dramatic effects on trading results.