original hem only useful to keep distressed hems. On raw denim there is no point, waste of money and actually worse than just hemming normal.
Chainstitch will please the denim gods, and might slightly improve resale, but in real life it will have little difference.
seriously just get them hemmed locally, regular hem anywhere can do it.
I agree with you on the original hem. They also look horrible if you cuff the jeans.
On the chainstitch, it's not the end of the world if you don't do it, but you do get better roping on your hems if you do.
Raw denim noob here, asked in the N&F thread already but i'll see if i can get more answers here
i'm about 5'7 and seeing that pretty much all raw denim comes in 33+ inseam which is too long for me, should I buy all raw denim in a waist size bigger than what i'm used to, and then shrink them down with washing?
I wouldn't do that. Most raw denim is sanforized (pre-shrunk), so that strategy wouldn't work well. The best thing to do is to buy your correct waist size and hem if necessary.