Your lighting in the latest revision is coming directly from the left, not upper left. (Else the south-facing walls would be in shade). But as long as that's consistent that's fine. (Which you're not just yet, but getting there).
i never really was good with the technical aspects of shadows, haha.
Your sprites are black and white, which is why they look out of place..
The castle is extremely bright and colorful in contrast to them.
the characters are supposed to be black and white (except for their clothes) because that's how they are in the webcomic the game is based on, with a few changes (like the hair on the red guy and the green girl).
they're meant to be like that (aracial) so that the fans can intepret them however they'd like and thats what i kinda want to do for the game.
Also, this looks like a mix between a pyramid and a castle, because of the yellow bricks.
I think if you swap the pattern on the wall for the floor, it will look more natural since that type of brick is used for walls.
As for the outlines, put outlines on the things you want to separate from the rest. You can add it to anything as long as there is a reason for it.
If you want the bookcases to be special, then keep the outlines. (but if they don't have any gameplay significance, why point them out to the player?)
you mean like this?

it does look nice n all but im kind of stuck to the original.
the bookshelves have some interesting bits of info as well as an item needed to make a new weapon.

Generally for the walls and such, add outlines where you want to create depth by separating for example the top of the wall from blending into the floor. Since it's harder to see depth and how things are arranged in 2D.
What you had done before was the opposite, where you have separated two things, the bottom of the walls and the floor, which are usually joined together.
its kind of hard to do this without losin the style. i could just change it like so.

Well shame on me from missing literally the first line in the first post.. 
aw geez dude, s'ok! you were just tryin to help, haha.
=
i dont really want this game to be TOO fancy, it is my first game and its just something for fun. no profit at all from this.
im working on windowskins/font colours because this looks strange (esp with the green girl)

but i have icons ready to go.

bonus title screen, background ripped directly from the webcomic.
