I have kept confined myself to major currency pairs not only while scalping but also while using other trading strategies.
before scalping in a proper way traders should choose the broker which allows scalping with no restrictions. otherwise scalping life could be worst.
Scalpers usually trade in shorter time frames. Since they need to be quick in decision, they should trade with pairs that do not have very high volatility. Major pairs, such as EUR/USD and EUR/JPY, make good pairs for scalpers.
this is so comfortable to scalp with all major trading pairs because of their comfortable trading spreads.
It is better to scalp pairs with minimal spreads to be able to earn even on a small price movement. That is why I often trade EURUSD, for which my broker fxopen has spreads of 0.01-0.02.
It's pretty good trading conditions but some brokers like HFM offer zero spread on EURUSD during London session, you pay only commission, so it is ideal choice for scalping. They can widen sometimes if you are "lucky enough" to enter during high volatility but still pretty manageable.
In my opinion EURUSD, GBPUSD can be good one to scalp, rest it is up to traders' option which pairs they find suitable for trading.