Good to see this.
I'm a beginner too as I think you know, so take with a grain of salt.

'r''s ...arm? ear? whatever you call that nonvertical part seems too light to me.
'k''s arm and leg both seem too light, too tapered, and the leg too casually curved
'j' tail's taper seems similarly out of place.
'd' looks narrow next to 'b'
'o' looks a bit diamond-shaped to me; is that intentional?

I like the character of this a lot.
Some of the bowls have a very appealing shape, and I especially like the ascenders - I think they can be a distinctive feature of the face without being distracting or unintegrated.

Keep it up!

This has promise!

In addition to what Craig pointed out...

The bowl of the 'b' looks too wide towards the bottom.
The stroke weights need adjusting. The straight stems are maybe a touch too thin compared to the curved strokes of the bowls of 'a', 'd', etc. The 'g' looks too heavy. 'o' looks a bit light compared to the bowls. The middle stroke of 'e' could stand thinning.
Conventionally, between the inner diagonals of 'w', the right stroke should be heavier than the left.

You might want to think about an overall plan of distributing weight on your strokes; letters like 's' suggest emphasizing the horizontals near the baseline and the x-height. Take a look at FF Balance to see what I mean.

Keep up the good work!

Well, I had a few hours to work on this font today so here is an image of the updated glyphs:

Now looking at this, the 'd' may still look a little too skinny.

eliason: Thanks for your suggestions! I hope that I fixed the 'j', 'k', and 'r'. The diamond-shaped 'o' was definitely unintentional, and I tried to make it rounder. Both you and Jongseong mentioned this letter, so hopefully it's better now.

Jongseong: I'm not exactly sure what you meant by "distributing weight", but I tried to normalize the stroke weights in all of the characters. Tell me if I understood you wrong or if I still haven't corrected the problem.

This is coming along nicely.
I do think d is still too narrow.
Are the counters of m equal in width? They look unbalanced but that may be the rasterizing of the graphic file.
Maybe extend k's arm higher and further (I think it can have some "overshoot"). To me this k still may be a bit of a misfit but it's better suited than the previous version.
You may want to thin the "crossbar" part of e a bit.

Much improved! I still think 'b' looks too wide next to the 'd', so you should try equalizing the apparent size of the two. With the new 'o', the 'd' is the one that looks rather narrow.

By the weight distribution, I mean an overall plan for which strokes would be thicker than which strokes. In the final paragraph of this PDF about FF Legato, different stroke weight distribution models for Univers, FF Balance, and FF Legato are compared, with an accompanying picture.

Sorry for the long delay, but it has been quite a busy week. I have put in some time into making the suggested changes, and I finished the set of lowercase glyphs. Tell me what you think.

As for the 'k', I made some alternatives. I'm not too comfortable with the third version, but maybe I'll warm up to it with time...

Hopefully by my next post I will have some capital letters designed but I'm not promising anything. I still have quite a few finals left and school doesn't end till the 12th.

I like the last "k". It fits in style and makes the face stand out from the rest a bit. The inner curve of "g"´s terminal needs a bit of fixing.

I think the first two are better!