I think it should be so tough to come up with a new design for a new Ultraman.
And the design easily tends to be the one with more decorations added to the original Ultraman.
So the idea of deleting, not adding, adopted for the Ultramans in the Heisei Trilogy is great, I think.
Without excessive decorations, I find each of the design well finished and attractive.
The Heisei Trilogy has the settings completely separate from the Ultra Series produced in the Showa (era name just before Heisei) Era.
In the Showa Series, the Ultra heroes were set as the Ultra Brothers though such settings didn’t exist in the First Trilogy (“Ultra Q,” “Ultraman” and “Ultra Seven”).
But, in the Heisei Trilogy, the Ultramans are not from Nebula M78, home for the Ultra Brothers.
(Ultraman Leo is exceptionally set to be from Nebula L77 of Leo)
It’s not clearly described where the Ultramans were from in the drama of the Heisei Trilogy.
But looks like they are the Ultramans the Earth gave birth to.
So they are not aliens.
As shown well in its name, Ultraman Gaia was depicted as something the Earth’s will made substantial.
And, though I’m unfamiliar, the Heisei Trilogy has attractive stories of its own.
It’s understandable that the Heisei Trilogy has ardent fans even today.