How do you assess architecture skills and maturity across your teams?

We conduct periodic workshops and self-assessments using a “Crawl, Walk, Run, Fly” model to benchmark progress and identify areas for improvement. This enables us to tailor development plans and ensure our architecture function evolves in line with business needs.

At my enterprise, we have a specific framework for evaluating and assessing Architects and Technology experts across both IT and Product Groups/Design teams. The evaluation is done by a committee of recognized and qualified experts at senior levels in the organization hierarchy.
Frankly we donot follow any specific maturity model but our own framework developed internally.

There are various dimensions of assessment as below

1) Technical SKills & Domain Knowledge 
2) Vision and Strategic thinking
3) Architectural thinking
4) Professional Certifications
5) Innovation, coupled with Patents - Maynot be applicable for all profile evaluations 
6) Communication skills
7) Collaboration with Peers within IT and cross departments
8) Applicability of various Architecture standards like TOGAF etc...
9) Papers, publications, participation and contribution in Industry conferences
10) Business Impact

Mechanisms of assessment include Self Assessment, Formal Assessment by committee, Mentoring and Coaching

Hi,
the first thing I would suggest is that you think about what is the contribution that you expect from architecture teams. 
Interacting with Architecture Leaders from different companies I have seen teams more focused on the technical aspects (breadth and depth of technology knowledge) while others are focused more on the business acumen and the connection with technology applied to the business. There is no right or wrong answer here, and probably a balanced mix of skills in the team will generate greater value for the organization.
What I normally seek when hiring and assessing architects start with soft skills: Communication, Collaboration and influence. These elements are key to have a good impact as an architect.
Architectural Thinking is the second group of skills: abstraction, holistic system thinking, long term vision.
The last part is related to strategy thinking and business acumen and normally it comes with maturity and seniority: industry knowledge, understanding business goals and strategy, correlation of business initiatives and how technology impacts and leverage it.
Best,
Carlos