Hi, I'm not an expert in the isometric style you've gone for, I'm a follower of the 4 pixel top and bottom of an isometric diamond style which works great when coding, but I digress...
The big house is very good, one problem I see is that your not consistant with the edge line of the house, the sticky out slanted wall's edge is not the same as the rest of the house. Other than that I can not see any major issues.
As for the little animated flashing light house, err the only thing I can see wrong is the base of the palms, but I think it's just a case of my prefered iso style to the one you have used.
I've just had another look at your big house, your defiantly mixing styloes, the floating H has some iso-artifacts at the bottom and is using the 3 pixel iso style, where as your house is using the 2 pixel style.