What about a company that would offer this for its consultants ?
I dig your first two points! I'd really like to have that where I work. Especially the half day to work on side projects. A friend of mine is working at a company where every Friday afternoon is dedicated time on side projects and learning new things... lucky bastard!
Another really nice thing would be the ability, for a consultant, to suggest things without being laughed at or being answered "You are just a consultant, you can't suggest things!". As an example, I like your Slack idea, if I suggested that to my employer, I would probably be answered with a plain and barely justified "No" (something like "that's not how we do things" I'd guess).
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