I'm looking to replace a Windows computer with a MacBook for work purposes: MS Office, Slack and Safari all in parallel. I would carry it in my backpack every day in a 20 minutes commute to work by subway, and since I'm a consultant I won't have a proper desk setup or an external monitor for my 8-9 hours typical workday. Would a MacBook 12 be enough or maybe the upgrade to a 15 inches would be beneficial for emails PowerPoint presentations and Safari browsing? Looking for comments of users who tried both machines... 13 is kinda in the middle so I would rather go small and light or big and full optional. iMac 5K at home for my Lightroom and photo video hobby.