Wow your going to have a long game with that many humans involved I got to say. Hope you set aside the whole day to play it lol. Max ppl i have played with in same game is 4 humans.
Random maps by their very nature do not in anyway make for a balanced game sadly. For some reason it never really works out.
UNLESS you use what is called a Random TEMPLATE. These Templates set certain boundaries for the generated map and will quite often give you very playable maps. However these templates were designed mostly for 1v1 or 2v2 player games 90% of the time.
Now you can get the Random Templates at the link below, copy/paste the link or type it out as sadly the main site has moved on quite a bit.
http://www.toheroes.com/h3maps/Random.htm TO USE these templates you will need to do the following.
1. Find the template you would like to use on the list, being sure to read the info on the side panel like map size and number of players.
2. Right click on the map picture and choose "Save Link As" (The pictures are only examples, not the exact map you will get)
3. Copy the file you have just downloaded to "C:\Program Files\3DO\Heroes 3 Complete\Data" Folder, or wherever you have it.
4. RENAME the file you have just moved into the Data Folder to "RMG" exactly, it will already be a text document ending with .txt.
5 Start up H3 and choose Random Map and setup the # of players and map size for your choice as long as it's supported by the template. (Don't worry if you choose the wrong size map or # of players it will give you an error msg saying so when you press Begin)
If you have any problems plz lmk.
NOTE - Most, if not all, of these templates Ban the spells Dimension Door and Fly as they made it a bit to easy to blitz an opponent without warning.
PS - Sadly the templates are only good for 2 or 4 players there are none there for more than that.
PSS - There are also fan made maps there as well. Just choose size of map at top right and you will see a list of maps you can download. To play these you would Download and unzip and put them in the Maps Folder.