Dont know If this has come up before in any discussions but have you guys considered link exchanging with one another to help on search engines etc? If anyone is interested I'd be happy to link you on my site-ofc it can be hidden in the background somewhere.
It would work out better for you if you set up one-way or reciprocal links from people like chiropractors, physios, fitness equipment etc.
That way you can benefit from targeted traffic (which is more likely to convert than from another PTs site), and have a more diverse backlink structure.
The more established the website is, the better the link, in terms of SEO and pushing your own site up the rankings.