Relating to shareholding clauses on milestones met or not, IP (ideas,patents) protected or stole , unfair dismissal or replacements of founders, team members, board members.
If your concerns are around negotiating between investors and the Company, the best thing you can do is to retain a great Silicon Valley based law-firm. There are about a dozen highly reputable firms that are very startup friendly that will often defer most legal bills or charge inexpensively during the startup stage.
I have recently gone through a complex transaction with one such firm, and was amazed at how great Silicon Valley counsel differs from other counsel I've used in the past. They are more efficient, more experienced and more connected than firms anywhere else.
The most important thing to ensure of is that the terms you agree to are standard and don't cause problems in subsequent financings. If you are dealing with a less experienced investor or perhaps less reputable investor, then they might ask for protective provisions that end-up turning more experienced investors off.
As it pertains to the fears around individual actors inside the company (management, founders, employees), this is far more an issue of employment law, by which things are fairly standard. All IP must be assigned to the company at time of employment (no exceptions).
With regard to unfair dismissal, that is a completely different matter and one that rarely ends well for anyone. If you feel you have been unfairly dismissed, then I would encourage you to consult a lawyer and get a 2nd opinion before pursuing. This can be costly to you with little to no actual gain.
Hope this helps and happy to talk further.