I'll work on the things you mentioned and work towards finishing this
Apart from the discussion about the shading/color/texture of the windows, I think a little reshaping of the windows might also make it look better:

- Example78.png (13.05 KiB) Viewed 5084 times
To me with the old narrower windows the lines dont always look/feel straight (even though they are), I think that an one pixel wider window gives a better effect, at least to me it looks a bit better

What do you think about that?
but had been wondering about the size for Delft Station which I think will be my next station before moving to Arnhem station.
the finished version of the station should house 4 tracks (it has two right now) so I was thinking at least 4 wide but how long should it be?
at first thought I'm thinking 5 tiles.
Well, your picture almost answers that question

Look at the size of the old station and compare it to the new one. The old one is already in a set and is 4 tiles long. I would say that the new one should then be 6 tiles long.
However I would preferr it to be 5 tiles long (to save a bit of space, you know me

), but if you are not able to get the shape correct on 5 tiles, 6 tiles would be good too. Elongations, if you have longer trains, can be done by separate single tiles that just have tracks under them and some eyecandy on top (like some of the metro-stations already in a set).
This may give you an idea of how it will look:

- DelftMockUp1.png (104.88 KiB) Viewed 5084 times
Note that I left some space between the busstops and the tunnel, that can be used for overlapping tiles to hide the tunnel. Also tiles can be included that overlap the tunnel on the other side of the station.
Also, google maps gives a nice view of the inside and outlines of the building, might be handy

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