You guys have been awfully lax on these over the years. You have two purpose-built routers plus the 565 cutting guide that made a third router....and yet you've had the same old six plain bits for the past twenty years.
Of course, the scale simply precludes miniaturizing full-sized bits. It's simply not possible.
What you *can* do, however, is this....
That's a simple mandrel with a slot in the business end. Into that slot, you weld a honed, hardened steel disk. Into that disk, you can turn or laser the router bit profile and the disk itself provides the sharpened edge. You can even extend the mandrel past the disk edge to form a pilot on bits that require them.