bricolage, I think pfredX1 has the basis you need for drilling small, precision holes. I was always taught slow in metal fast in wood when drilling. I do a fair amount of drilling in wood, a lot of it has to be precise and I made wood "center punches" from scratch awls. I re-ground the ends with about a 15deg angle and mark the location before drilling. It eliminates almost all of the "wandering" and I use very high speeds for drilling. I also have learned to sharpen my own bits. I think the biggest hurdle for me is ending up with a perfectly centered point. Relief behind the edge is pretty basic and I have separate bits for metal as these are a little more aggressive than my wood bits (I'm just basically impatient i guess!). Before modifying the machine, I would suggest different techniques first. All it will cost you is some time.