I'm no expert at programming or anything but maybe a happy medium could be brought about.
I'm thinking something like th 6x6 safe rooms thing, if you don't exceed a baseline size limit you don't have to worry at all, but as soon as you dig out a 7x7 area it starts making the fancy expert player spreadsheet of calculations stuff to determine weather a place will collapse or not.
Possibly with good miners, strong materials, skill, or a combination of those you could still have a 0% chance of a cave in. This would allow average Joe players the ability to still safely make areas without worrying about collapse, and allow the more experienced players the ability to make large or complex areas without having to worry about collapse due to highly skilled miners or stratigic use of good materials.
The safe area would probably have to be tweaked a little bit if there are more factors than just room size now, but it shouldn't be too hard to find the scenarios where your obviously safe doing this without worrying. Probly things like simple stalagmites would be perfectly safe but as son as you start giving them odd shapes or doing other weird things the collapse calculator begins taking notice.
I figure this would keep the new players interested while letting the artistic math wiz ones still amaze people.
Please pardon the run ons and stuff. It's 1:35 in the morning here and I'm out of Dr. Pepper.