Things I never thought I'd miss (but sometimes secretly do) about working outside the home for someone else:
Working in a team. That sense of shared purpose and 'all being in it together'. The feeling that other people know what it is you're doing and why. People who understand the same jargon and share at least some of your frustrations with the job. People who are, quite simply, there during your day and sometimes give you an opportunity to laugh and put things into perspective. (Which is a little difficult in a room on your own.)
Gossip and other people's problems. It may have been irritating at the time but it was a window onto another life and a way of bonding with another person. (Even if the bonding you were doing was with the person across the room who sympathised with you for being cornered, rather than with the gossiper.) It's easy to get 'stuck' in your own life if you don't get to see into other people's.
Meetings. An excuse to drink tea, eat biscuits and call it work. And still be paid!
Someone to blame. If a day is too busy, boring, stressful or just plain rubbish then it's the fault of the company, the workmates, the workload someone gave you... Never your own fault, surely.
The boss. Passing the buck. ("I'm sorry, I would have loved to help but that decision was out of my hands. Blame the boss.") But, more positively, being able to talk through a thorny problem or a difficult decision or a question you don't know the answer to with someone who, in theory, knows more than you and, in practice, can actually tell you what to do and make the burden of responsibility a little lighter.
Going home. The change of scene and pace; the feeling of escape and relaxation. How can you capture that feeling of going home when you're already there?