Diffuser is simple you can make them out of lots of materials . The ones that stick on the end of the light( like a traffic wand ) I really dislike because of the glare . They are hard to look at and almost need another shade over them . The best Diffuser is translucelnt material you just put directly on the lens .Works much better in my opinion.
Sounsa like multiple cheap lights is the easier way to go rather than looking for one perfect light ..Convoy S2 is a very easy light to recommend at 17$ and the jacob a60 for 10$ is also a steal right now too . the nitecore D2 is a good charger and any name brand(japanese) 18650 .
If you want to try a zoomie buy one of the 3.50$ ones from >>