As you have probably already noticed we avoid to make any negative criticism on the models featured on this blog, mostly because they are all really beautiful and wouldn't like to spoil the visual pleasure by nitpicking on small inaccuracies. Nevertheless our friend Cameron Lohmann was very open and positively receptive and therefore the purpose of the following comments is definitely not to put down his "Hayate" modelling effort but to help build better and more accurate models in the future. Feel free to leave a comment with your observations, questions or disagreements.
1. According to Akimoto-sensei IJAAF units that were officially entrusted with the air defence of Japan sported hinomaru with white bands on the wings and fuselage sides. Aircraft belonging to air defence units like the 4th, 5th, 53rd, 70th, 244th Sentai, the Dokuritsu 17th Chutai and others carried hinomaru with white bands. It should be noted that only units that were designated as "air defence units" carried the white band, not units that occasionally contributed to the air defence. An example is the 5th Sentai which in the summer of 1943 relocated to South-East Asia and its aircraft stopped carrying the white band.
Below are some examples that show how the bands, actually "bandages", covered completely the areas and didn't form "squares". All photos are from Koku Fan Illustrated #42.
Type 97 Fighter or Nakajima Ki-27 beloning to the Tachiarai Rikugun Hiko Gakko which had a small air defence group.
And finally a Type 4 Fighter or Nakajima Ki-84 "Hayate" belonging to the 47th Sentai also. Note how it seems to have a previously applied white ring around the fiselage hinomaru.
2. I would recommend to have the drop tanks painted the same colour as the lower surfaces (gray). Although yellow is a colour that has not yet been refuted beyond any doubt please visit THIS thread on Hyperscale regarding IJAAFdrop tanks.
3. I would finally recommend some stains and dirt behind the exhausts since it's an aircraft that has seen action.