I took my full bike test a few years ago (although I'm only a humble bird, I do live in Brighton!).
I found that bigger bikes are much easier to rid. They feel much more stable and solid because they are heavier, and you don't have to thrash them to get up hills on windy days, so the power is much more relaxed.
Loads of bikes come with "low" options. Try a few and see. When I passed my test, within a few weeks every bike dealer in Sussex was fed up with me spending all my weekends riding their demonstrators.
So go for a big b,ike but maybe look at a bike with a torquey engine (a big twin cylinder perhaps) rather than a revvy racing bike. In any case, big twin sound so much better.
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