Luka just going thru your parts BOM...noticed on DD10/11 you put in
RS stock 661-4591, a 6.2V LDO. The LDO is supposed to be 6V version, but ok 6.2V Vs 6V isn't much should be ok though. Just sayin!
Ok found another...VT3, IRLML6302TRPBF, is an extended range min order qty 50 @$.28 ea (50 x $.28 = $14). Alternate at RS is:
IRLML6302PBF, 610-6851, in Pk of 5 for $3.93 (@$.786 ea)...exactly same as other one as "TR" reference is just "tape Reel". So the alternate is cheaper.
Also its good to cross check everything! I'll do the whole BOM and check it against the parts on Schematic. I'll go thru all then do a summation post as posting everytime I find something is in dribs and drabs.