A 5 days 4 nights trip should be sufficient. Where to visit for photography? Sunset of the town and river from any high floor hotel facing the river, day and night shoot of the town including the riverside. Food - Top Spot and Green Hill Corner (Jln Green Hill)for seafood and hawker food. A good local 4 star hotel would be the Grand Magherita (reservations@rmh.my or phone60-82-423111) which was recently refurbished (formerly Hilton)around RM200+ twin sharing. Or on the cheap - the Waterfront Lodge,(admin@waterfrontlodge.com or Phone 06-082 231111) for Rm35 you get a bed right in the heart of town.
Bako National Park - Hostel bed for Rm15 or 2 bedroom (2 twin sharing) for Rm140 - all no aircond, only fans. The boat ride to the park is Rm20 per person return and you may have to walk out of the boat if the tide is low, so need to take off your shoes. There are 19 trails some short some long, do not hike in the hot sun, pure suffering. I really don't think you need a guide on those trails with a boardwalk. Get to see wild boars, probosis , silverhair and makat monkeys, snakes, insects, pitcher plants.
Damai Beach - a day trip will suffice and the Sarawak Cultural Village is located there, best to start off in the early morning like 7.30 am and get back in the evening as the hotels there are not cheap.
Caves (45 mins from town) - for those who like exploring, there is the small Fairy Cave (free entrance) and also the Wind Cave,(Rm3), but be prepared to climb and walk. Half a day should be enough.