1. No magic.

2. Multiple species, all nonmagical (reiterating the first answer).

3. Custom preferred. Not averse to pre-existing settings.

3.1. Science Fiction.

3.2. Myst (Not that anybody knows what that is (...And it doesn't meet my own listed preferences, but its the exception to the rule)).

4.
4.1. Only if we're in a well established setting, such as Mass Effect - where picking one particular nation/faction is a given.
4.2. Some people build the challenge into their own nations. Even when you don't, you still have to deal with everyone else's factions. There is more challenge to interacting with other factions created from scratch than there is interacting with other factions you already know will be in the setting, no matter who you get stuck with yourself.
4.3. See 4.1.

5. No.
5.1. Clarify and refine your question.

6. As an implemented feature, absolutely not under any circumstance. There have been instances where others and myself have used coin flips or dice throws to determine RP outcomes, but only in such a case where both parties wanted the outcome to be truly random. - the usage of chance wasn't mandatory. Making chance mandatory makes it an obstacle to writing.

7. While I say I prefer settings without magic, I am not averse to effects that are traditionally considered magic - such as telekinesis/mind reading/shape-shifting - in instances where such effects can be accomplished using technology. Having a setting where every nation is stuck in a medieval stasis and relies on apparently 'magical' technology might be interesting.