I'm not sure if I would ditch Zotero. Using grep over a bib file is nice but I guess you are opening the DOIs in browser every time?

The reason I like Zotero is because I can use it offline, have my all documents synced (the backup feature is one of the best things) when needed and I can organize my papers according to project/paper I'm working on. Actually one thing I do wish Zotero would add is tab groups which will allow me have papers open but grouped by project. It's based on Firefox which does support this so I hope it's a matter of time.