Broker Spreads and Fees Experience (Forex, Crypto)

Recently, I've been trading $EURUSD and $BTCUSD and noticed that spreads and commissions are much more important than I initially thought. Especially during volatile market periods, spreads can widen surprisingly. I'm curious if others who trade with multiple brokers have any criteria for choosing a broker that offers reasonable spreads and fees.

I understand that no single broker is best in all aspects, but if the focus is specifically on trading costs, are there any particular points to consider? For example, times when spreads widen the most, or account types that offer better overall value when everything is calculated. I'd appreciate advice based on real-world experience.