I think you should look into www.supportbee.com, it's like a smart shared Gmail account (even has the same shortcuts) and it allows for template responses and i

I think you should look into www.supportbee.com, it's like a smart shared Gmail account (even has the same shortcuts) and it allows for template responses and if you want you can connect with your other systems using their API. Disclosure: It's run by friends of mine but I use it myself as well.