Those are both ideas that can be used in interesting ways, but what
really matters is what is behind them? If the plague simply pops up
now and then it cannot be stopped.

If that is the case then you are treading a fine line between adding
spice to the world, and tormenting the players for your own amusement.

The same mostly applies to food shortages, if then happen because of
something the players can prevent then it can add drama. Players pretty
much always explore and look for new areas, but if the orcs block the
river it gives them a cause to fight for.

A.T
(-)

Having seen more than one time the effect of rampant diseases on a MUD, I'd say that the plague idea is a very bad idea. It is very hard to implement it in such a way that it has some balance.

As for shortages, I have never seen such an event make players explore. Instead, they whine and stop logging on until the shortage is gone.

hrm hrm and triple hrm..
if say,disease hrm..maybe some herbs growing somewhere which can prevent it ?
so that you ate a herb - you're not affected by it.. ?
and,hmm..well..why wouldnt food shortage encourage exploring ? i think its rather fun..

Players explore, so I do not know of much that would 'cause' them
to explorre cause it just happens.

I think you are just thinking in too broad of terms, trying to do anything
that affect a wide group, or all, players, is complex. Players prefer to at
least feel like their actions matter, they do not like to be played with.

If there is a logical reason for the food shortage, it might be preventable,
and there is a way to fix the problem, that would be a good motovator
for a small group of players perhaps.

But really, you have to define what sort of game you are talking about if
you want to really evaluate what works, even these things.

What Style of game, what is the basic gameplay focused on, if it is full
RP you have a lot more latitude in creative events, if it is pure powerplayer
then you are advised to stick with solid code.

A.T
(-)