Share User DB across Multisite

There’s a lot of plugins that just don’t do multisite very well and I’ve found that some like to be network activated while others need to be activated individually on each site. I must have at least 100 hours into trying plugins, deactivating all when something suddenly slows the site to a crawl or I get some kind of error. I keep a list now of what’s network activated, what activated on the main site only and what’s activated only on the subs and what’s individually activated on main and subs. If you search for “plugin auditor”, there’s a couple of plugins (because you need two more) that show you what’s activated where.
I’m running with subfolders rather than subdomains and things are going ok. I didn’t really have a choice on that as I have ssl but not a wildcard ssl which would cover subdomains. The only other type of multisite I know of is a networks of networks with lots of domain mapping but it’s not needed for just a few zones of a site.
How many plugins do you have? I’ve got 41 I active and things are still ticking along pretty good. Took me a while to gather that working collection. My subsites only show 3 active as that’s all that were activated individually one them. I’ve got 18 active on my main site and 19 network activated. Then 15 more inactive that I’m wanting to try out. One at a time, carefully with lots of inspection to make sure everything’s ok. Page speed tests etc. I don’t have buddypress but do have bbpress. Take a look at Ultimate Member as a possible replacement for buddypress.
I would keep trying with what you’ve got before rearranging install type. Changing multisite after it’s set up a certain way tends to lead to a whole new set of problems. I can post my list of plugins if you want. I’m using a note-keeping program to keep track of everything website related.
Yeah, that common suggestion, “try deactivating all your plugins and see if that fixes it” has a whole new meaning with multisite.

@drexlock: Your question was about creating three sites that would have their own instances of plugins, but share users and files. This is exactly what multisite does: shares core files, plugins and themes as well as users in one database, with each site keeping its content separate.

Here are the instructions for setting up a multisite network:
https://codex.www.ads-software.com/Create_A_Network

Hi jhnpldng

I was thinking of going to multisite for a few reasons, the one big one is different themes or layouts for each branch of the site. Each sub site would carryover a similar theme to the main site but have different layouts based on whats running on the subs site.

I was able to pull this off somewhat with BBPress using a different page layout but haven’t been able to do the same with BuddyPress. For some reason I cannot change the default page type used and the social icons plugin I’m using for blog posts keeps popping up on the Buddypress pages where they shouldn’t.

I’m a bit of a WordPress Newbie and have been able to work out everything so far but thought breaking the site into different subsites might be easier to handle going forward. But in reading the MultiSite instructions it might be a little too powerful for what I’m trying to achieve and seems to not be as friendly to cross site plugin/data interactions as i originally thought.