i've been surfing an nsp 6'6" short board for the last 4 years. it's great, but recently i got a catch-surf 5'6" skipper fish (foam) and now realise how heavy and cumbersome the nsp board is

i am comfortable on both boards (albeit extremely unradical), and the fish is awsm for summer waves and bigger waves too if they are clean, but it's very light and very flexible and i'd like a more stable board for bigger waves and windier days (i surf onshore 2-6 ft the vast majority of the time - mediterranean chop).
tbh i'm quite happy with the dimensions of the nsp 6'6" (20 1/8", 2 7/16"), and i love the fact that it's more or less ding-proof, but i'd like something lighter and snappier but still tough and with enough volume (i weigh 80 kg and am not getting any fitter/younger lol)
would really appreciate some recommendations as where i live is not very surf-orientated and there's no surf-shops or shapers, so i'm going to have to order blind online.
i was originally thinking about a larger short board, but considering we hardly ever have proper swell and very few reefbreaks, maybe a 6'0" fish or egg might be good? i don't really know much about shapes though.
i don't want a longboard yet, that will be the purchase after next (!). i don't have unlimited budget, but anything up to 400 should be ok.
many tks!