It looks great if you can do it on foot, though my plan to sail there to watch the fireworks has been shot away, as it seems great flotillas of Dutch yachties have booked all the nearby berths that can be found! Duh!
Over that weekend and the one before there’s quite a lot going on besides the fireworks, including living history events at Upnor Castle, Dutch and British warships, a a fun fair, food and drink stalls and a river pageant sail past the Dockyard and Upnor Castle. There’s also live music, walkabout entertainments and clog dancing performances will run throughout the evening. Check the leaflet for details!