Duffle Bags -
Have a separate duffle bags for undergarments or things which aren't valuable. That ways you know which bags are important, which ones aren't and high value items are kept safe in the luggage bags.
Power Extension Board / Power Strips -
Since we all carry multiple electronic device, it's best to carry a power strip which would ensure that all electronic devices can be charged at once, considering most of the hotels have limited power slots. I always carry a Belkin Power Strip which has been a time saver for me. It also has a Power Surge protector which has kept my devices safe as of now.
Organizer bags -
Carry a small Organizer bag which contains all your passport, credit cards and ID cards in one place. That ways you will be able to carry them safely while traveling.
A plastic box as organizer -
A plastic box to keep all your adapters, valuables, small items and anything delicate covered with soft cloth, all of that to protect your items from getting lost/ deformed as plastic box provides the protection against all jerks, etc.
Your fully-charged Cameras and mobile phones
Don't forget to keep your Cameras and mobile phones and getting them charged to 100% to ensure that you travel without any issues. Along with these, carry all your spare memory cards for your cameras too.
Buy or keep extra batteries and Power banks for your camera and digital devices -
You may not find power slots everywhere you travel to and charging devices can take hours. It's always best to buy and keep extra batteries and power banks to ensure all your gadgets are fully charged throughout your journey. I bought 3 extra batteries for my GoPro and Sony RX100vii, yes, these can be costly but not as costly as the budget of your trip and the time that you may miss out while charging your gadgets.
Duracell 20,000 mAh Powerbank - https://amzn.to/3OEIRv7
Duracell 20,000 mAh Powerbank - https://amzn.to/49x77XJ
Don't forget to pack your dental kit (Toothpaste, Tooth brush), Disposable bag, Shaving kit, Liquid Handwash, Wet wipes, Tissue papers that you might have gotten from any hotels that you might have stayed at. This is particularly important for the ones who goes out for long drives but is relevant for others too.