some are too stuck on caps and not noticing the important stuff.
Hintzy saw one, run wires behind the amp board! easy to do and makes it 100x better looking and safer. also, you should secure wires to the board, to provide strain relief when ran on the board surface. if a wire got snagged it could short out and cause damage to the amps, battery, even start a fire. sparks are plentiful In a short.
most important item that was missed: on the Pioneer amp you have bare copper wire strands visible and loose. dangerous. put a proper spade terminal on those wires. at no time should you see bare copper wire strands.
also, when you reduce wire size you should have the smaller wire fused unless the amp includes fuses. not fusing a smaller wire means it could be overloaded and get hot, then melt, then short out. the amp fuses will protect from overloading and the fuse at the battery protects from short circuits.