> 2) Import this into some kind of database that I can easily search whenever I need to [hence not just a local copy on Thunderbird for example
Presumably the OP wants to be able to search when remote from the thunderbird instance.
I use Eudora for checking, searching and non cloud archiving, then Gmail as a spam filter and the basic view for sending the odd email.
> 2) Import this into some kind of database that I can easily search whenever I need to [hence not just a local copy on Thunderbird for example
Presumably the OP wants to be able to search when remote from the thunderbird instance.