@expertalmost,
I've generated a working solution and just wanted to post it for future generations
Someone pointed out that because the data is not really fall under "standard error" due to the gaps, that medians +/- stddev would not really work. I have confirmed this with many days of attempts.
Therefore, the other typical solution, as far as I can tell, is called rank-type smoothing or moving quantiles; with damping of the end result. Basically, using a sample size of 100, I take an average of the 10 largest items for the maximum and an average of the 25 smallest items for the minimum. I then dampen the changes to 10% for smoothing. This gives me a smooth enough maximum and minimum line to use as a 0-1 scale.
Hope this helps!