I'm a HUGE fan of multiplayer games. Not having people to play anything more difficult than RISK when I was a kid, kind of stunted my growth in the 'pure' war game, i.e. hex and chit, but, I do love to play games against human opponents. The vast majority of that mp goodness is digital.
Now. Having been (rightly) accused of being a sore winner AND a sore loser growing up, I am acutely aware of how my play style and demeanor comes across when playing against human opponents. So much so that I usually don't play as ruthless as I am. When I play a game, it is to win. Period. Playing well and fighting the good fight along the way is important, too, but, winning is the reason I play. However, that doesn't endear me to my opponents and they are less likely to come play again. Contrary to my reputation, I try not to agitate my neighbors and declare war. So, I usually slow play whatever game we are playing and try to set up an overwhelming force of arms so my opponents can see that and decide if it's worth pursuing the game to the end.
Something else I encounter is, the team up. I talk a good game. And in the games I play frequently, I have enough experience that I can usually back it up. The people I play against know that and many times will overtly or covertly, team up against me. That's ok. If I can take on the combined might and intelligence of two or more players and STILL eke out a victory, then all the better.
Finally, the thing I encounter MOST in mp games is apathy. Most times, guys only have an hour or two on the weekend to devote to a game. And I am fine with that. It's cool of them to take their precious time and play something we all enjoy. However, because we tend to play games that take several several sessions, it gets tough after a while to keep every one committed. People go on cruises, or to Vegas, or banana republics for five or six weeks at a time and then the game is kaput. Once, I would like to finish a game we start.
As for the issue of 'down time' in a game, it's a double edged sword. Every game I have mp'd with fellow grogs, I have gained a reputation for taking a loooooooooooooooooooooooooooooooooooooooooooooooooooooooooooong time to take my turn. It's partly deserved. I have a clear idea of what I want to do and how to do it and there are just some times that you can't be rushed. In return, I understand when an opponent takes time to complete their turn. That part is always forgotten in the, "MD is glacial," chatter. It would be much better if all involved were in the same room, but, through Teamspeak or the Steam voice chat function, we can chat and laugh and devise plans to our hearts content while someone is taking a turn. And that is priceless.