You've pretty much got this house done perfect, i like the overall shape of it, but the walls are my biggest issue, as a rule you should try to not use 1x1x5 bricks to build entire structures with. instead of usinf those partucular peices try using larger peices or even some of the shorter, longer bricks such as 1x4 bricks. This would greatly inprove your overall building skills, also when you think of building things IRL what sounds more sturdy, staggard 2x4's or lines of 1x5's?
but overall the house has great shape and design aspects.