I feel I should fight Minsmere's corner!
I am from Suffolk but currently live in Norwich, so can give a fairly rounded opinion. I love Minsmere, but right now there isnt a great deal to see. Minsmere itself is fantastic in the spring, but can be a bit quiet in winter. However, if you work that area of the coast you can pick up Twite and Snow Bunting at nearby Walberswick, and if you are lucky the Penduline Tits (no sign today though). Benacre broad is also worth a look. You can get close enough to birds at Minsmere, so from a photography perspective there isnt much in it.
Cley is great for sea watching right now, as is anywhere along that stretch of coast. There are usually more waders at Cley, if that floats your boat. Close for photos too.
Right now, I would probably check out Cley, and tie in a trip there with other sites along the coast. However, if the Penduline tits put in a show in the morning, Minsmere and the neighbouring sites would be back in play!
Whatever you decide, you will enjoy a good day no doubt.
Cheers,
Jim.