As stated in a previous posting there are several things that a trustee needs to be aware of - the first one is the organisation's governing document. Depending on the form that the organisation takes this document will have different names. A company has articles and memorandum of association.
The memorandum of association sets out the company's name, the proposed location of its registered office, a statement regarding the liability of its members. It also contains the company's object - that is, what it does. However since October 2009 it is possible not to have a restricted object for ordinary companies - but for a charitable company the object will need to be restricted to charitable purposes - which is about public benefit. The articles of association (often just called 'articles') contain the rules for the company's internal regulation and management e.g. the meeting schedule, who can call a special meeting, the quorum for meetings, what happens if the company needs winding up.
Most of our chapels and meeting houses will be unincorporated associations and so will have constitutions. I suspect that many of these documents are decades old. Here is Charity Commission guidance about constitutions.
Trusts have trust deeds.
So first, have a look at the governing document and see what you can and cannot do as an individual trustee and as a board. Is this document fit for purpose or could you update it a bit to (a) fit more accurately with how you actually do the governance now; (b) ensure that you have covered everything that you currently do; and (c) is clearer for trustees and others to understand what the organisation's powers are?
Don't rush headlong into wanting to change the governing document but keep it in mind as something you might like to do consider at some point in the next year or two. Then have it on your list of things to talk with other trustees about.
Whatever changes you may have in mind ensure that you are familiar with what it says so that you may work within it.