Hmmmmmmm - this could get complicated very quickly - i would recommend specialist advise to go through all aspects of how vat will work now for each business. i don't know where to start on the various areas that could be a complete nightmare in this regard.
Some random thoughts
If someone crowdfunds you and gets a free ticket to a concert that would be vatable supply - i suspect there could easily be a vat liability on funds received via crowdfunding.
Are services "of others you engage" vatable it will depend are you acting as discolosed agent / perhaps you could be.
could there be partial exemption issue - if the services provided are exempt - then possibly yes
could there be vat leakage if you bill out income on a vatable basis for artists costs - yes.
If you bill private individual customer £20 for juggler show and pay vat on that sale then pay the non vat reg juggler (working for you) £20 you are out of pocket via the vat as the default position.
Do you know what the VAT/income tax position is with these sources of finance? It wouldn’t be income to me personally but would go to hiring actors/crew, rehearsal space etc.
The problem is the default situation is that income paid to you is yours and vat may be due on that income - unlikely for grants but if you are providing any sort of service for money received it sounds dodgy.
Note it could go the other way that you can claim back input vat without having any vat leakage in which case this might be a good plan.
From a simplicity and financial safety point of view though for you - starting with a separate limited company that doesn't have the obligation to immediately be vat registered presuming turnover is modest may be the least headache option while offering you from protection - if for example a venue had you ticket sales money and then went bust on you - much better a liability like that not being in your personal name if that might be an issue.
can't say i have ever really dealt with a theatre group and vat so there are probably others better placed to offer some more practicable pointers rather than my random thoughts.
Oh i just found this random article too