If you have a large number of customers then you can definitely go for Raiden Network or Plasma as you only spend a small amount for fees rather than spending for each and every transaction. Moreover RN/Plasma allows you for fast, scalable, off chain and very low fee transactions which is too good for people like you as you do lots of transactions.
Raiden/Plasma is more superior to Lightning as it supports all the ERC tokens and smart contracts whereas Lightning supports only btc. These are great solutions for ethereum which has been facing a backlash due to sudden increase in miner fees and this could help the currency reach great heights.
I think you should have posted this topic in altcoin discussion as you have been discussing about eth and it's fees here. (correct me if I am wrong)