I totally get the pinky dangle struggle... it drove me nuts at first too. If you want something that works well without breaking the bank, I highly recommend the SmallRig L-Shape Grip for Fujifilm X-T5 4060. It adds just enough height to the bottom so your whole hand actually fits on the body. I have been super satisfied with it because it makes the camera feel way more secure without adding much bulk to the setup. To stop the stress about dropping it, I also use the Peak Design Slide Lite Camera Strap SLL-BK-3. Honestly the anchor system is the only thing I trust for safety when I am out and about. It is really easy to adjust and feels very reliable for a big trip where you will be walking a ton. Those two combined really fixed the handling issues for me and I havent had any complaints since.

Ive spent way too much money trying to get my Fuji bodies to feel right over the years and basically figured out that a thumb rest is non-negotiable. I use the Lensmate X-T5 Folding Thumb Rest and it completely changes the leverage you have. It makes the camera feel way more secure since your thumb has a physical hook to hang onto, which is huge if youre used to a beefy Nikon grip. Another small fix is a soft release button. Try the VKO Wood Soft Shutter Release Button. It sounds like a gimmick but it helps your finger find the shutter faster and improves the tactile feel. Also, for your Japan trip, definitely grab a spare Fujifilm NP-W235 Rechargeable Li-Ion Battery. Third party ones can be hit or miss with the newer sensors and you really dont want the camera dying halfway through a day in Kyoto.

Like someone mentioned, grips help, but you might want these:

• SanDisk Extreme PRO 128GB UHS-II SDXC
• Expert Shield Screen Protector Fujifilm X-T5 Gotta have UHS-II for those 40MP files tho.