I had the displeasure of running a D365 setup in a small government agency that took about a year to get off the ground. It was a living nightmare and I would never recommend D365 under any circumstance because of that experience. I'm tempted to say you would be better off using a free or homegrown CRM than choosing Dynamics.
A few lowlights (Disclosure: we were in the government cloud which is notoriously far behind the commercial cloud):
* Had to hire a PFE to set up the Exchange integration. This should be turnkey if you are in the same company's stack, IMO. Instead it took thousands of dollars and days of work by the PFE, our centralized Exchange admins, and myself.
* Little things like hiding the freaking nav bar cards are literally disallowed in Dynamics.
* The Dynamics 365 App for Outlook is a dumpster fire that didn't work at least half the time. Search queries returning no results, no useful error messages, and an overall appalling UX. It single-handedly killed adoption.
* I spent many hours trying to figure out how to send timed emails. That's because you have to use the advanced logic tools which are a nightmare. I was able to spin up the same timed email in SFDC in a matter of minutes. I truly wish this was an exaggeration but it's not.
* D365 documentation is utter garbage when compared to the SFDC Trailhead. The only option for getting off the ground for our technical staff was to pay for training through one of MS's sketchy vendors. It was overpriced (about $3k) and not at all great.
* The only way to programmatically interface with D365 APIs is through using the ancient SOAP API or their REST endpoint with OData syntax only.
* Oh BTW, if you were hoping for a modern development workflow, think again. You are going to be stuck manually uploading files into Dynamics for things like editing the internal interfaces of Dynamics. Oh and you have to register every single function against every single trigger, manually through a GUI.
* Their customer facing website options are a joke. I can create a fully fledged web app with complete control over the HTML/CSS/JS using the SFDC community, this is definitely not the case with Dynamics. You are limited to the point of only being able to choose layout templates with Dynamics. The last time I checked, you couldn't create your own.
* The development workflow with Dynamics is a joke. With SFDC I get a passable command line tool, multiple VS Code extensions, an easy deployment path, local development with Lightning Web Components, and many other developer tools. Good luck finding any of that with Dynamics.
The above probably could have been shortened to say the following: SFDC is dedicated to CRM while Dynamics is another in a long line of MS products and it feels like it.
I know there are problems with the SF platform, I feel them daily, but I don't think comparing the two is fair to D365.