Hey,
Since many rooms has a unique features, I think randomly spawning items (buildings, towers, 20lumber, 50lumber, 1g, units?, etc...) would suite Storage Room quite well.
On the other hand, current Easter Eggs are wayyy too strong and I suggest they'd only spawn in easy-mode. For example you can find an easter egg with 5g+500lumber just few minutes in to the game, if I recall right. One can't even spam all of that into lumbermillupgrades, because not enough mills
Bounties would be smaller but more frequent, also another good reason to take a walk outside the base
Greets,
KeXi