I had the same inclination as you. Dropbox was cooking my 2015 Macbook Pro. What I can tell you might reduce research time.
Google Drive has no differential sync. Any changes you make re-upload the whole file. This is a hard no for me. Also Google.
I moved to Sync[0]. The pricing tier was more what I wanted (500GB). They support symlinks, differential syncing, selective sync as well as a 'Vault' for storing files in the cloud but not on your machine. I think it's end-to-end encrypted as well, not going to commit to saying anything specific in that regard. The Mac app is also a lot better, I find it spinning up a lot less for me and its a lot lighter in general. To be fair though, even with iCloud I get my fans whirring up when I start uploading lots of changes.
I've also heard good things about pCloud[1] but I don't see any reason to change my workflow now after have to already change it.
Sync claims that, if you have the Sync setup create your own encryption key on your device, files are end-to-end encrypted. I believe them. Moreover, Sync support confirmed that they do not have access to meta-data about your files either. Thus, their admins do not have access to your unencrypted files or information about them.
They support all the usual devices both on the desktop and mobile apps.
Their servers are located in Canada, not the U.S., if geography matters to you from a privacy perspective.
I will also second that Sync seems much speedier than Dropbox. Startup / connection time is maybe 50% faster on my dated machine. (Dropbox seems to say Connecting... forever!)
You can run both Dropbox and Sync.com at the same time if you want to migrate slowly. I use Dropbox for non-sensitive files (e.g. rando family pictures) and Sync.com for sensitive files (e.g. birth certificates, financial files). With Sync.com and their more thorough end-to-end encryption, I feel safer that my file data cannot be used for random studies or anything else Dropbox feels like they can justify [0].
Google Drive has no differential sync. Any changes you make re-upload the whole file. This is a hard no for me. Also Google.
I moved to Sync[0]. The pricing tier was more what I wanted (500GB). They support symlinks, differential syncing, selective sync as well as a 'Vault' for storing files in the cloud but not on your machine. I think it's end-to-end encrypted as well, not going to commit to saying anything specific in that regard. The Mac app is also a lot better, I find it spinning up a lot less for me and its a lot lighter in general. To be fair though, even with iCloud I get my fans whirring up when I start uploading lots of changes.
I've also heard good things about pCloud[1] but I don't see any reason to change my workflow now after have to already change it.
[0] - https://www.sync.com/ [1] - https://www.pcloud.com/