As a lightweight like you-I would not go for the Aksiums. I have a a pair but they are stiff and I do not have enough weight to keep them on the ground. Son-in-Law has though and he loves them---Especially as he hasn't bought them. The Ultegra's- as Mobile has said- do not have to be used as Tubeless. They are a good weight for the price and really well built. They ride well and although low spoke count are not fragile.

I have been using Merlins for 20 years now and they are well known for their handbuilt Mountain bike wheels. Their 105's to open pro are also used within my local club as they are cheaper and as well built as the Good local wheel builder.

But plenty of wheel builders and builds out there.I would always recommend handbuilts to anyone Provided the builder is good. They seem to add something to the wheel that is not possible with a machine built. They know the product they are selling and the use they can be put to. Their reputation is on the line and they know it so do not sell an inferior product.