Granted the Brits give you that +1 advantage but within my Brit army I've used a full HT army, a mix of shooters-tanks-artillery, a mix of shooters-artillery-APCs, mix of shooters-APCs-bazookas, a mix of APCs-artillery-regular tanks.
Just because you're British doesn't mean you can't experiment with various combinations, the Brits simply give you a great fall back option, especially if you include the 15% extra loot.