For what it might be worth, I've been here just coming up for 3 months and my wife will hopefully be joining me from the UK once all of the house sales, etc., are all tied up - and I can empathise with your concerns.
But I agree with everything that's been said above - especially about the walking speed, escalators, etc., but then hey - I'm not 'at home' anymore, and I've also come to realise that one simply needs to adjust. This is all part of life's learning process, and rather than getting bent out of shape about it, it's far easier to accept life as 'different' and enjoy it.
Before I came, I was told something quite profound - 'the opportunity of a lifeltime lasts only for the lifetime of the opportunity'. So do it. Regret only those things in life you don't do, and put the rest down to gathering worldly experience.
Singapore will be what you make it - warts and all. But you won't find an easier, safer or cleaner place to live in Asia - do it and enjoy it.
Pierson