In my view, 1 month is an overlong suspension, as others have said. That person won't be back, unless he/she is really desperate and/or entrenched.
Do something like 2 official warnings for initial infractions, a suspension of 1 week for a third infraction, making clear that this is the final punishment before a full ban. If that's too lenient, make the progression 1 warning, followed by 1 week-long suspension, followed by full, final ban.
That's just my little input on that subject.

And then there are the indefinite suspensions. I've seen bumped threads from YEARS ago which have suspended members posting in them, and their last posts were literally years ago, yet their accounts still say "suspended". What's up with that?

They never came back to ask if their suspension was over and the Mod forgot about them?

Would it be possible when someone is suspended for, say 1 month, to change their title to "Suspended until **/**/2013"?

That is a great suggestion. Many of us only know each other from here and don't know any other information that would at least allow us to anticipate their return.