Something I have always done, and Sue who I live with, has always taken the 'mickey' out of me by doing so, and that's having a 'packing list'. I have one for every trip and it's set out in order. Titles are toiletries, clothes, tickets & paperwork, and miscellaneous. Can't understand how anyone can organise any trip without their packing list....but we all have different ways of doing things.
I am going this time with just 1 small rucksack, which I use as my 'carry-on' luggage. Then I have a very small suitcase I use for the outward journeys for my 'hold' luggage. On the return I then use my small suitcase as my 'carry-on' luggage (make sure it's small enough for all your flights dimension wise, mine is 55 x 24 x 34cm which is ok for KLM and Nok Airways. Whilst in Chiang Mai, I then purchase a suitcase to use on the return journeys as my 'hold' luggage.
I do the above because when you visit Thailand you only need your toiletries, 1 change of smalls, iPad, Camera's and assorted chargers etc, when you fly out. Don't do what some people do, they take a small wardrobe with them! When you are out there you buy things as you need them, then bring them home. A t-shirt in Chiang Mai costs less than £1 so why take more than 1 with you.