[>BKA< T Wrecks]

That's what I did when I started... then I tried to cut it down a bit and waypoint more efficiently... and then came the new editor which allows to switch max. connection distances wherever I want to, so that I can insert many waypoints in narrow and important areas and few in open and rather unimportant spaces. Now my waypoint files tend to be a tad smaller than right when I started, but usually bigger than the ones during my "middle phase".
And I know what you mean with the size. However, my limit is 30-40 kB; if it doesn't have more than that, it must be crap. Even on a small map. However, after waypointing cs_psychobilly I found the file to be 47,4 kB, and I think my stuff doesn't suck that hard usually, so files don't need to be huge in order to be good. There are also some 100+ kB waypoints that suck. Or the one I had for cs_snowflake: It was @ 1000 nodes, but some areas were hardly waypointed. Ok, it's a GIANT map, but still... I always thought I could do better, but hesitated at the propect of making such a huge file... then I did it, and I ended up @ 800 nodes and had everything thoroughly waypointed.
Oh, and you can calculate the relation node count / file size roughly like this: 50 nodes = 10 kB, i.E. your average 450 nodes WP would come in at 90 kB.