Following feedback ony previous post, i thought i'd ask this question next. This would cover all locomotives from Classes 70 (SR type) and 71, 76 & 77 and 81-92. Not quite as many to choose from but some superb machines are to be found here.
Any of the 81 to 86 series would be wonderful, especially in their original light blue livery with the cast aluminium BR lion and wheel crest. They looked great with maroon coaches and could be seen alongside diesels in green livery and steam locomotives. Or, in the 1970s, BR blue livery. Somebody let me know if they ever make such a route and I'll buy TSW2.