Medal and mission feedback does focus on individual needs, that’s the point of it. The mission guides the learner to the improvements that they personally need to make.
I share some of your concerns, grading achievement is known to have a detrimental effect and needs to be used with caution as I describe above. Also educational management and government focus too much on crude measures of performance such as tests league tables and inspections, those countries that do best in international comparisons of education systems focus instead on the professional development of their teachers, and they provide the support and the time that this needs. But there is nothing wrong with students achieving, that is the purpose of education.

Hi,
Good question. Medals should be specific rather than vague:‘You answered the question very directly’ is much better than ‘good answer’. ‘Your use of metaphor was powerful and appropriate’ is better than ‘there is some very good writing here which I greatly enjoyed reading’.

Missions should be forward looking and positive for example ‘read questions more carefully’ is better than “you didn’t answer the question which asked for three reasons to irrigate”. Similarly ‘check your spelling before handing it’ is better than ‘lots of spelling mistakes here.

Some teachers like using assessment proformas examples of which you can download from this page https://geoffpetty.com/for-teachers/feedback-and-questions/
These make the goals really clear though they would be made clearer still if you showed students examples of good work, explaining how they met the assessment criteria. Another helpful strategy is to ask a class to mark the same piece of anonymous work using your assessment criteria, followed by class discussion. There are many other methods in my books related to medal and mission feedback.

The goals need to be supplied by you usually, but the medals and missions don’t, use self-assessment and peer assessment, which can be done in small groups.