1) When you are in the world map, you can look using the L key and arrow keys, and find the city! Of course, sometimes there may be a convoluted route to get there and you end up going the wrong way, but it does show you where it is. That's something I only learned after many characters starving to death as well.
2) Yes being burdened makes you hungry faster, and it makes your legs stronger.
3) Yes I think it can happen randomly any time you enter a new level. There are some certain cases where it won't happen but I can't think of them right now.
4) I'm not sure about the difference between necromancy and resurrection. If you used a resurrection wand then yes he would definitely be back and you can play with him (but can't control him much).
5) For INT and WIS you can raise them both by raising scrolls and books, that is the easiest way. INT is most useful for hardening your item materials.
I just updated Somagu's original post with all of the new ideas. I'll get working on them when I have time.
Erno ever get a chance to make that magical mushroom smiley? The animation would be hard.