this is a very cool thing to do, but i think some of the characters are a little too wide.
i'm sure that "l" would work fine it it's lower bow would be cut at it's half width. same for "j".
the "t" could need a cut of one or a half brick on it's left side...

also, i think "r" is a little too long on the right, the result in "empty" room in it's typeface, same for "s" but not as strong as in "r".
Please don't get this as an overload of critism, but this could just be PERFECT, man :)

Without question this is great work, and the upper case is FLAWLESS, baby!