Have you tried the touch adjuster (a little tab under the hood, toward the front of the machine)? They are extremely effective on this model. I think the lowest setting is best; the highest turns the keyboard into a very tight trampoline. When properly adjusted, I think the SF is an excellent typewriter.
I have it on the hardest setting on purpose because the lower ones felt too slow, but not just slow. It's really hard to try to describe without making words up. I'll try the lower ones again for extended use and see.
I'd try thoroughly cleaning the segment and such with some electric motor cleaner / carburetor cleaner / or such. Maybe put a hint of PB B'Laster on the typebars. They ought to be quick and snappy even at the lowest tension setting.
This typeface from Olympia, apart from being a fairly standard serifed design, is incredibly clean and beautiful. It is also great to read. I never expect these travel typewriters to have a very good touch, and I don't use them very often. I do like the styling of these machines, but I honestly don't care too much for them to chase one down. I may be missing out on something, but I guess I have too many Hermes Babies and Adler/triumph tippas as it is.
Their 11 cpi typeface is definitely beautiful. It, along with Olivetti's standard elite and pica, are some of the most beautiful standard typeface designs.Anything smaller than a Lettera 22 or one of the small Brother portables usually is too small for me. I'm finding that out along the way. I enjoy them, and they look great, but I don't find myself compelled to type with them much.