Forward drains:

Starboard drain tube:

Port drain tubes:

As you can see, also on the port side are two additional glassed-in tubes, previously for raw water and sink drain. The PO filled them in with thickened epoxy.
The aft port drains go through the bulkhead and drain into the lazarette (and thence through a one inch hole forward of the outboard well).

Water comes through them in following seas.
I recently bought four 1.5 inch Perko cockpit drains off Ebay (for the extraordinary price of $20 apiece).

So I'm thinking about for the aft drains, and filling in the existing drain holes and installing one of the new 1.5 inch drains in each corner. Something like this:

connected to two above-the-static-waterline through hulls in the counter (beneath the aft end of the cockpit sole (perhaps crossing the lines for more room).
Space is limited there, and I'm not sure there is sufficient room to also install seacocks.

For the forward drains, I'm thinking about either sealing them up (and depending solely on the two new larger aft drains), or installing the remaining two new drains to above-the-static-waterline through hulls (perhaps with seacocks; and perhaps with a T for the deck drains).
In any event, I'd like to cut out the old glassed-in tubes and properly fill the holes with new laminate.
So, among my questions: (1) anyone have any thoughts on this plan or wish to suggest alternatives; (2) am I crazy to install the drains without seacocks above the static (but not heeled) waterline; (3) can I do the hull patching entirely from within (I'm in the midst of painting the topsides, and may want to put the whole drain project off until next year, but would do the drains first if delaying would mess up the new topsides finish - current drain exit is below the raised waterline)

Thanks in advance for any thoughts.