I would agree, and have said repeatedly, that propane isn't the best solution for SERIOUS heating requirements away from the dock. On most boats, diesel(preferably of the Webasto/Espar variety) or kerosene is likely the best solution for those requirements.
As always, nice job spelling out the trade-offs John. With regard to SERIOUS heating requirements away from the dock . . . I did also consider this in deciding between the Newport Dickinson P-12000 vented bulkhead propane heater and the Webasto Air Top EVO diesel heater. SERIOUS for me however, means long term away-from-the-dock heating (but with routine access to marinas for reprovisioning), but still either seasonal use (if up north) or use further south, NOT a requirement for living aboard year-round in Nova Scotia or similar (now that would be SERIOUS!).
The higher electricity demands of the Webasto, it's higher initial cost, greater installation complexity, and further loss of my already limited storage space due to having ducting run through the boat, pushed me in the direction of the P-12000. I have a smaller boat though (PSC 34), so I'm not in the situation where I'd need two bulkhead heaters.
Agree, this is definitely a case where the best solution completely depends on the specific boat and usage requirements. Regardless, there's issues that apply to all cases, such as guarding against oxygen depletion and excess moisture, avoiding inconvinence (e.g., for me - carting wood), etc..