In reply to Sensato Serif:
Good improvements overall.
The serif-'a' needs a hand on the upper terminal. The terminals of 'c', 'r' and 'f' are well accomplished, but in 'a' the terminal doesn't return inwards (sorry for the pleonasm), but it stays in the same angle and gradually tends upwards. The consequence is a hanging terminal. I also see you've aligned it with the bowl from the left side†. Often, the terminal doesn't hang as far to the left as the bowl††. As for the terminal of 'y', it looks unsteady†††.
The serif lengths are not consistent. Particularly, the upper serif of x-height letters could be longer (see /qu/ pair).
Nice 'd'/'q'.
† And why did you change your mind? They weren't aligned before!
†† The uttermost example could be Diotima. If you take a look at the opposite extreme, I don't know any 'a' that hangs more than Caslon's.
††† Can you post a PDF or a bigger image of the character set next time? I wanted to look closer at the upper right of 'z' :-)
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@hrant
For me, the term 'usable' embraces almost all existant fonts, but I think you're referring specifically to text-font usability.
Some well-known designers never produce anything really original their entire careers.
I'm curious about which designers do you mean by that, but naturally, it's something you wouldn't be posting in this forum :-)