Gmail or also the e-mail provided from google I think is the best email you can get, for so many reasons:
Most of the people use Skype to make calls with faraway friends and family, by the way, I find Skype so obsolete, and slower! Google+ has the function google hangout where you can do video conference calls with more people and you can add effects and chat etc.. from a regular browser, without having to have to open an other app or software, google offers free calls to US numbers and exceptional rates to call landline phones and mobiles around the world.
The mailing list can be very useful especially if you're handling a lot of clients and or a blog or whatever you need to send the same mail to a lot of different people. There's the option to connect your address book from your iCloud on Gmail and having all your contacts there, every time you receive an email to someone you want to use to a specific target of the user just add him to the group. HOW?