Just to link back to the point from Sean about the side ring sword and dagger above, I think the sword is an early form of Northern European 'pillow sword'
https://www.clevelandart.org/art/1916.1495. These vary in size and substance but the style matches and the blade form does too except the later 17th century ones generally had smaller hilt bars and crosses and lighter blades.
This one is a bit more substantial and has the matching dagger, which I think puts it outside the later and lighter pillow sword group as daggers as a set with swords had pretty much died out by the 1680s. Pillow swords with this hilt style were around from the early 1600s and I think this is an early example and in a period when daggers were still a common accessory with a sword, hence the matched hilts. The dagger is a fighting weapon by its size and length I think. It isn't a general use knife/dagger or a sneaky back of your belt type of dagger.
That's my guess anyway. Some aspects made me think they were 16th century - the blade on the sword for instance - but my gut feel is early 17th. Could be an older blade remounted possibly. Also the hilt is a bit too baroque for the 1500s I think.
They are a nice set - compact but quite substantial weapons in mass. The sword would serve as a good cut and thrust weapon. It is in a way like a mini-arming sword in feel, per your point.
It's interesting that I have seen some people associate pillow swords with the development of smallswords. I don't agree with this and think that view is driven by the fact pillow swords were shorter than rapiers and so they associate them with the trend for shorter and lighter swords as fencing styles changed. But the ones I have handled (not that many to be fair so anyone shout if they disagree) are compact but quite robust and have weight in the way the early smallswords do not because of their purpose. I think the smallsword developed entirely from the light weight transitional rapiers of the second half of the 17th century which got lighter and shorter as the century went on. I have quite a few from that period showing the development. I will post a good early example from about 1660. I think pillow swords were a different group personally but happy if others disagree