Try some deficit pulls standing on a 100lb plate. They work great for conventional pullers.Those and some heavy rack pulls will help you smash that 500 barrier.
imo a deadlift is a deadlift... yea you did hitch it a bit so it wouldnt fly in powerlifting, but in the increasingly popular strongman, there would be no question that its a GOOD lift...
peeps have criticized my pulls on here and even gone as far to say they 'dont count' because my back would round just a bit like yours... it a MAX EFFORT lift people... if your back doesnt round a little, then quit being a pussy and put in a bit more effort...
if it goes from the floor to standing upright its good in my book...
good luck on the 500... i will tell you its a barrier that sure did fuck with my head for a while, but once i passed it the first time, other small gains seemed to follow much easier...
i need to start doing these again... your vids are motivating me to get back on the platform honestly, i havent done a meet in about 10 months... just been busy with my family and just been 'staying in shape' i guess...