Hi Scott,
The forthcoming addition to Learning Plans of an Evidence tab may help with that.
You may also be interested in the work the Totara team have done around Open badges and the wider concepts of how that may start influencing accreditation and the display of a learners' achievements.
http://steverayson.kineo.com/2013/02/open-badges-moodle-totara-join.html
http://www.slideshare.net/dajbelshaw/open-badges-rocket-fuel-for-the-accreditation-of-skills
http://www.openbadges.org/en-US/
http://docs.moodle.org/dev/openbadges
See https://www.totaralms.com/feature-a-benefits/roadmap for an overview of what is coming
Other suggestions in the current set-up.The learning plan has an Objectives tab that could be used to include objectives/achievements in a manual way. They would need manual completion according to the objective scale you assign and according to workflow permissions - a manager or the learner marks them complete for example.
This would be visible in the learner's record of learning - My Learning > Record of Learning > Objectives
They can also be reported on using the report source Record of Learning- Objective Scale.
I am sure other users will come back with some other suggestions...
Andy