It must be free in belief, intellectually open, critical and generous. In other words, critical faculties are involved in the worship. Spiritual practice is at the heart of what the church does, its beginning and end. If it does one thing only, it is to provide opportunity to reflect, contemplate and find moments of otherness from the usual, all in order that the usual can be better faced.
The church must be inclusive of categories of people traditionally despised. Its ritual life needs to be feminist and across sexualities. It needs to develop a breadth of loving fellowship.
The church needs to have an ethical focus, including on the issues of the day. It needs to think socially and environmentally. It thinks in terms of justice.
Its worship needs to be broad in sources, including a critical use of these sources, whether from the Christian New Testament, Jewish Tanakh, the Bhagavad Gita and Upanishads (etc.), the Buddhist Sutras (etc.), other traditions and new material. It needs to use those sources directly and sensitively, aware how the use changes them, and not to do violence to their original settings.
Figures of the past, who built tolerant churches, can be listened to again. What did they do in their day? How does that relate to freedom, reasoning (and being reasonable) and toleration today?
The church sets out to use language and symbol to find signals of transcendence, and maybe transcendence itself, the holy and the numinous. It should identify forms of religious experience. It debates how people come to fulfilment, including through loss to self and an exchange of the material for the spiritual.
The church can be democratic, but needs to be so in a liberal manner, looking for consensus where possible, acknowledging difference that exists.
It should be able to use Francis David's statement, you need not think alike in order to love alike, and the idea is that a fellowship can encompass difference, just as society needs to tolerate difference.
The church needs to look ahead more than much as it looks back. We live in the now, informed by the past, but the future is the destination.