What quiescent current draw of my circuit would be acceptable for a 100mAh battery?
This is actually a rather straightforward calculation, but you might need more data than 
provided.

Wikipedia says LiPo has a 5%/month self-discharge rate, so even with zero current draw you have 20 months standby.  5%/month * 100mAh is about 7 uA current draw.  

So we'll say the combined discharge at 10 uA is 17uA.  100mAh / 17uA = 5900 hours standby time.  This is about eight months.  Is this sufficient for you?  If you knock your standby down to 3uA you can get about a year standby.  

Notice that all these calculations are assuming a lot of things.  You won't always be in standby mode if your circuit does something useful, so you should add in active current * duty cycle.  And of course battery chemistry is complicated, so these are just ballpark figures until you actually build and measure the circuit.