I tried toning and bleaching on a few of the 'rejects'.
Toning I simply steeped a bag of tea in hot water from the tap for a few minutes. I tossed the tea and print into a shallow container. It soaked for 5-10 minutes. The color is somewhat 'Diesel' denim or brown/black, depending on the observer.
Bleaching I also did a bleach test. I mixed a heap of baking soda (naturium bicarbonate) in some warm tap water. This bleached the image clean off the paper in a matter of seconds. I know it works, but I have not tried to tune or control the process.
Improvements My UV source is too close to the paper. Rather than getting over developed spots, I get light-ish underdeveloped bars where the reflector doesn't adequately distribute the UV light. This will probably be fixed by raising the UV light a few inches over the paper (of course this will throw off my exposure times...)
Conclusion I'm really really pleased with my results. My images were not washed off by the Amsterdam tap water (my initial concern). A total lack of precision chemistry didn't hamper my ability to get great prints.