Transom starting to go. Looking for advice

[madangler]

The transom is starting to go on my 1973 SC 20' CC. Bought the boat last August and repowered it with a 150 etec in October. The transom has been fine sonce we bougt it, but today, while pulling back the caulking aroung the aluminium plate on the transom, I found some fairly substantial cracking.

I do a lot of 20+ mile swordfishing runs often in slopy seas so that has no doubt put some serious wear and tear on the boat. I the plate and transom around definitely flex when I put weight on the moor, and when I apply weight I notice that the crack opens up for a good ways down the motor well.
Basically I am looking fo advice on the best way to go about redoing the transom. Wondering what anyone's thoughts are on repairing /redoing vs closing up the transom and adding a bracket I'm not dying for extr space, but it would be nice to be able to walk around more back in the stern. If end up redoing the transom now would it need to be done yet again should I choose to put in a new floor down the road? I have a 40 gallon bait tank that tends to flood the scuppers a bit, would a bracket/rerouted scuppers make the boat much drier with the tank full? Whatever I end up doing, I will be looking to have the work done rather than do myself. All advice is welcomed. Thanks