In scalping the trader usually sticked with a pair that is most volatile example BTCUSDT or ETHUSDT with low commission for crypto while in forex trading trading pairs lsuch as EURUSD, GBPUSD and USDJPY are mostly with low spread, however scalping require maximum concentration and focus by the trader because it involves a short movement of the price and precise entry and exit is the most factor to considered by an experience scalpers however this comes with numbers of years and skills, thus it is not advisable for any newbie to start trading as a scalper else such a trader will rekt their portfolio swiftly.
There are different trading strategy one can use to bring profits from trades. Scalping is one of the worst strategy for newbies to adapt to, but it's very essential and good for experience traders who knows the entire formation of scalping. It's one of the tough method to use in trading because it blows forex accounts easily and run down futures trading accounts into liquidation. I wouldn't advise anyone to start scalping without undergoing well equipped PDFs concerning scalping. My favorite pair is EURUSD pair and it's absolutely understandable.
Talking about scalping regarding the ideas that you guys have articulated here, I want to say that one dangerous thing about scalping is it can blow your account easily that day trading or swing trading. With day trading and swing trading, you are a little prepared and guiding yourself with the caution of using stop loss but most scalpers don't use stop loss just because the scalping time may not allow for it and that makes it dangerous. Again the network can become an issue if you are already in scalping, if the network goes off then you can't control your order which is a problem because the trade will keep going on and before your network is restored you may have lost your funds.