I would say the LHT and 520 are similar , the component pick is a bit different.

you can shave weight off what you have by taking off the suspension fork, and replacing it with a long bladed suspension corrected fork , ..

A faster type of ride is Brevets , the grandaddy is Paris Brest Paris.. bike with a light but cushioning tire in say
a 32 width fairly slick, 700c or 650B. a light thin wall tubed frameset
drop bars a good sized Handlebar bag and a Largish British saddle bag is a pretty classic setup..
Velo Orange in Maryland, has been offering gear for that style of machine, for a couple years..
mudguards of polished aluminum racks bags frames, components , etc..