Back and Forth
Well, I have gone back and forth with the whole inboard, outboard thing. Several things finally swayed me in the direction of cutting out the transom:
First, many of the E27s came that way from the factory, and the owners of these boats seem to be happy with the performance. And I was basically re-constructing large portions of the boat already, so this wasn't a big deal in terms of additional work, materials, etc. (and I discovered a large amount of water in the transom which was freezing and thawing and tearing the transom apart!)
Second, outboard systems are less complex (not the outboard itself necessarily, but exhaust, fuel, electrical, mounting, drive systems etc.). I like the fact that when something fails on the engine I can simply unbolt the motor and take it home and work on it instead of contorting myself in a small, hot and damp space.
Third, I can carry a small backup motor in the boat, ready to bolt on if the primary fails.
And fourth, cost. To fix up my A4 (without a full rebuild), would cost approximately $2k. And I would still have an un-rebuilt A4. Yes I might be able to find a used diesel for around the same amount. But I would still have to put another few thousand into it in the form of controls, exhaust, mounting system, prop and shaft, etc. I can get a good used outboard for well under $2k.
Finally, performance. I sail on a river which rarely sees large waves, and it will be rare that I actually need to motor for long periods of time. Also, I am planning to be out more in the cooler months, and having my kids be able to sit in the cabin without a deafening roar from the inboard (and worrying about CO poisoning), will be really nice!
So for me, it seems like the correct decision. I realize this is not the case for many (if not most) other sailboat owners. Hopefully I won't regret it. And if I do, I'm not going to admit it!
Doug