Separate the communicate and management issues. Also separate the model, financials and cap table pieces.
Cap tables should not change that often. The only times you should see material changes in the cap table are when you do a new financing; do a major revision in the equity comp plan; cross a major threshold with conversion of debt or option/warrant exercise/expiration; or have a recap. Minor changes due to the grant or revocation of options and warrants would not normally be a material change and don't merit special communication.
As a CFO you should be maintaining your cap table continuously and update it constantly. One technique I use (but rarely see used by anyone else) is to have the vesting and expiration dates all falling on the first or last day of a calendar month or, better, calendar quarter. I also prefer to have all Notes in a class mature on the same day. By doing this it gets easier to manage the vesting, expiration and maturity processes and the cap table stays cleaner. There is also less room for dispute about the proper definition of maturity dates, anniversaries, etc.
Ideally the financial model is driven from an assumptions table and even more ideally, a summary of major assumptions inputs and key results are presented in a nice table so scenario analysis is made easier. This is helpful as long as you are not changing the way the model itself works.
Each time you change the underlying model I recommend saving it as a new, numbered or dated version. Make sure you keep a list of the changes you've made. If you are using Excel or an equivalent designate a sheet with this list of changes. This gives you the history to know what happened to the model and when.
Financial statements probably come out your accounting/bookkeeping system. Almost all such software produces standard financial statements and offer lots of ways to customize. I always start with QuickBooks Pro and when the company becomes complicated enough to merit something more robust than QuickBooks Enterprise we look for software which may be more customized for the industry. If you have good disciplines you should be locking prior periods as time passes and changes to history should require administrative access and sign-off.
As for communication, minor changes to the cap table or model generally don't get discussed beyond management and the Board. Major changes to the cap table are usually something shared with shareholders as the funding round is planned and generally require approval or at least notice to shareholders. You need to describe major terms and outline the financial and ownership impact.
Major modeling changes are generally shared only with the management team, Board and shareholders who have the right to get this level of detail, normally only VCs or strategics and Directors. Normally I would send out a summary of changes and the results of some key assumptions and the summary results. Unless an investor has the right to have access to the model I do not recommend sharing the live model - there are too many ways for someone who does not understand how the model is built to have something go wrong. I will do a live session with someone who has reason to play "what if" scenarios.
All financial information including model results and financial statements should be shared periodically with everyone entitled to see them but all documents should be PDFs, not live Excel, Word or Powerpoint documents.
Hope this helps.