Underwater shape obviously makes a big difference.
Long keel with cutaway forefoot (like our Albin Vega) means you can pretty much sail or motor over anything with impunity (and indeed Vega sailors I met in Ireland often do, as it can save a tedious trip round the long salmon nets you often come across on the W coast)
Fin keelers with the propshaft on a P-bracket can get into serious trouble if they either don't have an effective rope cutter or don't stop the engine in time, as the propshaft can twist and tear the (often remarkably fragile) p-bracket out of the hull. This happened to a friend of mine just off Eastbourne - he caught a hefty bit of floating line and was towed into Sovereign Harbour with the boat rapidly filling with water. He lost a week and about a grand in repair costs. This was on a delivery from NE Scotland to Tenerife, and the ironic thing was he had just fitted a rope cutter for the first time in many years of sailing . . . sadly not the best design, as it turned out.
(The boat was a Moody 33S Mk1, not noted for their flimsy construction . . .)