I equate spicey/peppery with perique and some orientals. (But it very much depends on the orientals. For me, Basma-forward blends are deliciously sweet, Yenidje is more like incense, Drama and Smyrna a bit more acrid to my palate.) I think you'd be best served by blends that have no perique whatsoever and focus on lighter orientals (or have no orientals at all).
The whole range of Virginias and Virginia/Burley flakes is open to you. Unless you can better identify which tobaccos are giving you problems, I think you're absolutely safe to explore any of the straight Virginias and Virginia/Burley flakes from McClelland, Rattray, Pease, etc. Just avoid any that also contain perique.
I don't think I've ever heard latakia described as peppery/spicey, but that might also be behind your perceptions. If that's the case, you might appreciate a lighter English that puts more focus on the Virginias and keeps the orientals and latakias in the background. (I tend to avoid these, though, so I don't have any good suggestions.)
I hesitate to give many recommendations beyond the biggest companies, since I have no idea what's available in the UK. Anyone else?