A long time ago (2010) I have started a new typeface written in METAFONT (see
http://www.typophile.com/node/73827). I interrupted the work because I had to investigate further in METAFONT and parametric type design (e.g.
https//www.tug.org/TUGboat/tb37-3/tb117romer.pdf or
https://tug.org/TUGboat/tb35-1/tb109romer.pdf or
http://typedrawers.com/discussion/2342/funtauna-rectangular-slab-serif).
But I have never abandoned the original project and have always been working from time to time for this typeface. Taking the updated METAFONT sources, I have produced some master fonts. At the moment, work is concentrated on 2 of them: The display face and the tiny face.

I have refined both faces in Fontforge and have interpolated the optical axis Tiny-Caption-Regular-Subhead-Display:

The intended use of the typeface (which I call Elemaints) is the use in scientific texts. The glyph forms are mainly based on french renaissance antiquas like Sabon or Albertina. The x-height is equal to the x-height of Times New Roman. The proportions are very similar to Minion. Therefore, the look of Elemaints may resemble Minion, altough every single glyph was constructed freshly. One intended difference to other french renaissance antiquas may be the serifs, which always end rectangular:
Elemaints is not meant to be a revolution but a free antiqua with optical sizes for scientific texts.
Any suggestions (except kerning, which is not done yet) are welcome (glyph shapes, proportions, rhythm, details, spacing, ...).
Comments
I'm getting the impression that the spacing is still a bit uneven, especially in the «Heavy boxes» Display text. Perhaps a touch too tight for small text in general?
As for letter shapes, the /a strikes me as a bit pinched/pointy on top, and I'm not too fond of /a terminals that curve into the counter space, but that may just be me.
Do the new optical sizes go in the right direction?
What optical adjustment need to be improved? Width? Darkness? Contrast? Serifs? Joints? Ink Traps?
I have increased spacing for the Display face (whitout any manual adjustments yet):
(upper image = old, lower image = new)
Would you give it even more space between the glyphs?
I did not understand the expression «Heavy boxes», did you mean counters?
"Heavy boxes" referred to the text settings in the examples you posted.
I will have a look on it again...
(Garamond gets away with a super-narrow /a design, but it is helped by the extra space opened by the rather generous outstroke.)
As for the spacing, I was actually referring to the «Heavy boxes» sample text in the Display cut, especially the /e/a combination:
What do you think about the spacing? What about the narrow/wide a?
The "ea" combo seems tighter than most everything else. The "new" spacing of "ea" is a decent match for the "old" spacing of the rest of the font. But because you make the "ea" combination the centerpiece of much of your spacing demos, it is hard to judge overall spacing.
I'm curious to read the MetaFont sources too
Will you use the SIL Open Font License?