If just going fast is your thing then the Thames isn't for you above the Barrier I'm afraid.
However there is loads to see and do and with a bit of local knowledge you can moor up whilst visiting a pub or Starbucks for an expensive coffee!
Good places to go include;
Teddington Riverside - Pubs and restaurants
Twickenham - Pubs and restarants
Richmond Riverside - Pubs and restaurants
Mortlake at The Ship - Pub
Chiswick Pier - Restaurant
Putney Embankment - Comedy shows watching rowers sink cars and crash into things.
Chelsea Imperial Wharf - Moorings, heliport, restaurants and hotels.
The Pool of London is rather berift of moorings but there is plenty to see. Once out the other side there is;
St Kats Pier (has sheltered us for many hours FOC) - art galleries, bar, restaurants.
Limehouse Basin - (free to lock in & out) - restaurants and pubs
So that's a starter for ten for places to go and don't be put off by horror stories about how fast the currents are. Plan ahead and use the ponies sensibly and you'll be fine.
The PLA have vids on how to navigate safely -
and a leisure specific website