Just a general thought.
I play several games that all have a save option and some of them take weeks to play.
But, I can't see someone playing a single text adventure for that long.
Some games could have randomized parts so that every play through is different,
while others are the same thing each time to allow the player learn and get past "kill" points.

So... what's everyone's take here?
Long game or short one?
Same set map and events or random events that makes every play through new?

Back in the days before the internet, there were only three options to get hints...

1. Ask a friend who was also playing in the hope that he/she had solved it.
2. Post on a Bulletin Board in the hope somebody would help.
3. Write and post a letter to your favourite computer magazine, then wait until somebody else answered and the magazine published the reply.

All these meant that you were playing for quite a long time. Also given that adventures weren't free and actually cost money to buy, you (and the authors) needed to ensure that you got value for money and would come back for more.

I still prefer these types and SAVE GAME is a necessity.

However, these days people want instant gratifaction. Therefore most games are small and can be played through in a couple of hours and there is plenty of online help available - forums, walkthroughs, etc.

As for maps, If it is a long one, than the map needs to be static along with any events. (In case it gives instant deaths) Hence SAVE GAME.
Short ones and one room types have their place but these are for the here and now crowd who generally race through without reading everything thoroughly and usually with a walkthrough close at hand.

My opinion may be different to others... but you did ask.

Long is good. As long as it’s a good game. As long as there’s not a ton of guess the verb type stuff that keeps you stumped for a while.

Mostly short is better. Smaller window for errors.

All-in-all, as long as it fits what I like, I’m good with whatever length!

Text-adventures can vary from game to game, and some are extremely long. However; if there isn't a longer version of a game, you can make your own, but it may take some time. For this instance; your game has a long story to interact with. I am currently experiementing on making long gamebooks to play, and I am writing them in HTML on my Ubuntu laptop computer.