The Touring seat should certainly help a little bit but don't expect it to be like a comfy Sofa.
As regard to the handling, it could be worth at some point getting yourself along to a suspension set up. The lightness at the front may be a consequence of the bike squatting back too much under acceleration. Worth a go and for £40-£50 it should be worthwhile.
Great that you're having fun on it anyway and it's more fun after the first service.
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J.JP
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My Mum says, there's no such thing as Monsters.