I use Safari most of the time on my iMac/Macbook, I like it because I can 'share' things like logins on MacOS and iOS devices with the 'KeyChain'. I also use Firefox for other WWW stuff, mostly FFA.
I use
Spark as my email client, mostly because I use a bunch of email addresses and with Spark I can use a 'smart' inbox that gathers mail from all of them and sorts them by importance that I have previously laid on them. (Personal, Notice, and Newsletter) This allows me to keep the advertisements that I want to look at, but not in a huge rush, separate from the more important email that I may get from my mom or my Amex or something like that.
Let us know what other specific needs are.