RBS Rewards and Barclaycard rewards are just like amex rewards. I rack up 300 quid on amex without trying and then usually make another 50 or 60 across BC or RBS.Hmm. It's £2 a month though right, and £9 back for two direct debits. Not sure what the 'Rewards' £1 is. Seems a bit of hassle to open up yet another bank account for £7 a month if I don't use the Rewards.
I use Amex wherever it's accepted for Avios, when it's not I use the Chase debit card for the 1% cashback which I pretty much max each month.
RBS primary - open it up during cashback period.
Main spend - amex
Secondary - BC rewards (excellent/best for travel too)
Tertiary / when rewards available - Monzo
Rewards on BC and Monzo are like amex rewards it just means you need to do a quick scan to see what's going.