Kmail suite for mails, cloud… (Switzerland ) they have a free plan (15GO for the cloud, and the cheapest paid plan is 2e/month for 1TO (20e/year ).

Threema for discussions (Switzerland) . the application is 5e, definitv not cheap for an app, but it is a one time paiement.
Swisscows (Switzerland), mullvad Leta (Sweden) as search engine. => they do not use their own index system but brave or google (you can choose for mullvad)

All those options are Europeans and have strong privacy policies.

I like /e/OS, but the app lounge bothers me a lot. There is no uninstall button and it is not possible to add Fdroid repos… So I have Fdroid installed in addition to it.

I do not see an added value as if I had the aurora store installed + Fdroid.

IMO, the best addition of e/OS compared to lineage is clearly the tracker /ad blocker app.