I've been playing with badges for a short while now and there are a few things I'd like to see implemented, if possible, that I think would probably be of use to others as well.
1. Upgradable badges - students can earn different, upgraded versions of the same badge. The new version will replace the old one.
2. More badge criteria - at the moment badges are awarded on completion of certain activities or awarded manually. I would like to see badges which were awarded automatically based on scoring a particular percentage on a quiz, or even getting one particular question right (though this might be a little more challenging to implement well).
3. Badge Award Pop-ups - something a little triumphant to tell you you've won a badge instantly rather than waiting for the email.
4. Be awarded the same badge multiple times - like a gold star for excellent work. You can then measure progress against others by how many gold stars you manage to collect. There could even be another badge for 5, 10, 20 etc. gold stars. For example.
I've been reading a few of the other posts as well and I realise that some features are difficult to implement due to the Mozilla Open Badges integration with regard to the rules placed on the badges by Mozilla. I'd like to suggest that an option be added to remove Mozilla integration. Now I know that the entire point of the badge system seems to be to make them transferable but I would argue that for many many Moodle users this is a superfluous feature that they, or their students, simply will not use. I speak from the point of view of a UK high school teacher who runs a number of Moodle courses and I can't see any reasons why my students would want to save their badges, export them to Mozilla and be able to add them to CVs (which is what I understand the Open Badges system is actually for), except bragging rights.
When I invent a badge to be awarded to my students the reason is motivational; they will want to collect them and this will inspire them to complete more of the work and to complete it to a higher standard. Pupils love xBox Live achievements and the badge system mimics this for them, which is an absolutely brilliant thing to do. This means I will invent a lot of badges for some seemingly quite trivial things such as being good at a particular topic, handing in work on time etc. The English department has one for 'using 5 semi-colons'. My point is that an employer need not know about these and they need not be exported. Allowing a badge to be 'unexportable' might allow many more, desirable, badge options to be included which would increase student motivation ever more, which is the main reason I use them whether or not it was the intended outcome.