Limiting what's visible in Dynamics 365 for Outlook

I'm currently setting up what's visible within our Dynamics 365 for Outlook app. I've gone through and adjusted which tables are visible, limiting it to just Leads, Accounts, Opportunities, and Contacts. I wanted to know if I could limit what's searchable / doable even further. I'm currently trying to accomplish two things:

1. Limiting the searchable records so that it only shows Active Leads/Opportunities, as it currently shows both open and closed ones and we don't want older, closed records to appear in the search
2. Removing the ability to create new records from the client, either via the '+' button in the top bar, or through the form when opening the record (see photos below)

Any insights as to how I can achieve both of these goals would be helpful, as I have been looking through the app settings for a few days but with no progress on these two fronts.

Thanks!