It can be slow to dry seeds thoroughly in humid weather and prevent mold. Seal partly dried seeds in a tightly sealed jar with a desiccant like silica gel to get them down to 15% eRH, which will give them the longest possible viable lifetime in storage.
You can bottom-water seedlings right in their tray if you put a fuzzy capillary mat between the pots and the water-holding tray under them. Add only a little water at a time, and the mat will carry that water in equal amounts to every pot or cell.
"OP" means "Open Pollinated", but that term is used in two different ways. It can mean an inbred OP variety that can produce seeds that come true to its parents. Or it can mean that a specific batch or packet of seeds labeled "OP" was "openly pollinated by wind, insects or birds," without saying whether other varieties might have cross-pollinated it.
When soaking seeds prior to germination, or when watering seedlings, use 0.1% Hydrogen Peroxide. This cleans the seed surface and discourages mold, fungus, and damping off. Drug stores sell 3% Hydrogen Peroxide, so dilute that 32:1. It is also great for plants already in the ground or in containers.