Reminds me a bit of Gill Sans somehow, which is a good thing.

E and F too wide, D too narrow, K and L too wide, P too narrow, bottom curve of S, X and Z too wide.

e, k: too wide
t’s descender too long and sharp?
v and y too narrow, x and z too wide
bow of r too flat
Q’s tail has no equivalent
top serif of J is not needed

my 2¢

Traditionally, the center stroke of the S is supposed to be thicker than the arms.

I like the relationship between the small x-height and the narrow caps (but some aren't narrow enough). This could possibly become more than a learning exercise.

Many of your curves are wobbly - look at the "e", and the top counter of the "R".

Some things:
- The "Q", "g" and "s" are out of character. For the "g" you might try a Koch form.
- Bottom of the "s" is too thick.
- I actually like the "t" being tall (especially in this modest-x-height design).
- The "x" and "z" are top-heavy.
- The little notch in the "y" is too tentative - dump it or grow it.

Last but certainly not least: spacing is a bit tight (and uneven).

hhp

Thanks everyone for the comments. I'm reworking the spacing* and fixing the curves on the glyphs at the moment. Things like the top heavy z was something I didn't see, but now you've mentioned it I see how it makes the character look top heavy with the equal widths.

I'll look at the other 'problem' characters as well; I find the 's' one of the trickiest to do. In terms of the Q, what other characters do you look at to make an equivalence in the tail?

I'm do like the Koch form 'g', so it should be fun to try that out. I didn't go with the "standard" single-storey 'g' because something about it bothers me, I can't explain exactly but it can occasionally trip me up when reading something with it sometimes, usually in roman sans-serifs. Strangely, it doesn't bother me half as much when it's in a blackletter style typeface; I don't know if this is due to personal bias, something quirky with my eyes/brain or something else.

*I think sometime I must have shaved off as many as 10 units from each side of all glyphs as an earlier version was much looser (probably too loose but I went too far the other way).

Optical adjustments are weird. They don't make sense mathematically.

g looks amateuristic to me.
bowl of /a/ could have a more horizontal flow
/e/ doesn't relate to /c/ nicely.
In /k/, the top diagonal appears thicker than the bottom diagonal. Optical illusion that needs fixing.
/v w y/ too narrow, and uneven stroke thickness. Same as /k/
Shoulder of /n/ (same goes for all n's relatives) : Move the two nodes (inside+outside) on the top to the right, for about, hmm, 10 units. Move the two nodes on the right down for about 15 units.
What I said about optical illusions goes for all diagonals.

Nice Q f and c! Keep it up.

Thanks, I'm working on the redrawing the 'g' when I can get the time. Strangely this to one of my old classmates and they really liked the 'g'.

You can certainly like the "g", but then everything else has to have that mildly dorky look.

hhp

Redrawn the 'g' and 'e'. I'm not sure if to go with these, and I might draw another later. The curves are still a bit dodgy, which I'm going through and fixing:

The "g" on the left isn't bad for an open-bottom form (which is hard to get right since there's less of a precedent so people don't just accept it unthinkingly*) but it's too playful here - you need to figure out how to tame it (maybe make it more rigid/rectilinear). As for your second "g", the advantage of the Koch-style form is its ability to accommodate a short descender (while avoiding a "g" that looks way too small**) but that's not the case here, so... A way you can still use it though is making such a "g" look larger - by making the head larger (although that might clash with the overall character of the font). And in any case you should consider removing the spiky part in the middle. Look at Ernestine's "g" for a very successful Koch-style "g":
http://ernestinefont.com/

* To me the closed form is actually inferior.

** Any binocular "g" must look at least slightly small, otherwise bigger things go wrong.

hhp

Revision 1

I'm still doing a few alternate glyphs to see what they look like with the rest (like the 'g') which aren't shown here yet. Mostly I've been fixing the curves, and I've re-done the spacing again.

Spacing still seems too tight to me in that pdf, but that might depend on your intended sizes for this.

As a general rule, would text sizes be somewhat more loosely spaced than display? is there any recommended reading on the subject?

New g is awesome :) Spacing is indeed still a bit tight. Compare it with existing fonts of the same style.

Done an update, loosened the spacing a bit, and done a few more characters:

PDF: http://typophile.com/files/some_text.pdf

The eye of /e/ looks cramped to me; I would consider lowering the crossbar.

Quite pretty!

While the |g| certainly looks nice on its own, it adds a certain cheapening Trebuchet-ness to the overall appearance of text.

It's been said before, but the cut-off of the |e|'s tail looks like a mistake. Those on |a 3 5| have a milder version of the same problem. I'd suggest bringing those in line with the straight cut-offs that dominate the rest of the letters. |6| and |9| look tilted, probably because of their slanted cut-offs.