Hi, Welcome along. Good looking bike and for once no evidence of oil drips, best check that tank!!!
Front brake hub lever is set over center, in other words the more you pull, the less leverage is applied. The angle between cable and lever should approach 90 degrees, but never go over 90. Rear brake lever looks to be set OK. Plenty on the forum about the brakes, which are known as "Full width cast iron hub". Earlier bikes have a half width 8" brake, considered to be good, or Full Width Alloy which BSA used for just a couple of years '56/57...not so good. The contemporary A10 uses the same type of front brake as yours, but with a bigger drum.
Fenders, tail light and headlamp mount indeed look non standard. Shocks and ride height will affect the ease of getting it on the stand, which is always awkward to use, but there is a knack. As you get into it, you will find many of the parts interchange over the years, thanks to BSA's continued development of the range. That all changes into the 1970's, before it all went down the pan.
Swarfy.