I think FPS problems are linked to using problematic objects (bad .msh files and so on), the density of objects (try to put too many buildings in a very large city, you cannot fly over it), possibly the number of different objects types you use in your map (good ones seem to have a smaller object set).
In my experience, actors.static is relevant when loading the map first, a big one would take a long time to load or a slow computer would fail to open the map. I use agkt_Karelia map as a reference,it has actors.static files between 6 and 7 MB. I would think you are ok with 257 kB.
You also have to think about who you would like the map to be for:
- Not so young computers often run by not so young enthusiast => FPS is critical to them.
- On-line players or interceptors/high level bomber minded => They tend to not care much about ground detail.
- IL-2 stock players => Using non-stock objects will be a problem for them.
- High spec PC owners who are also modders => you can throw anything at them.
I am in the last category. Although I do not have a monster of a PC, I built the machine last year and get 60 FPS easily. I am also only interested in Eastern Front where you fly very low and ground attack is the main activity. So level of detail, graphical gorgeousness (see VPMedia work) and historical accuracy are very important to me.
If I ever get to release
anything it will be "4.12.3 CUP compliant" + "4.13 Asura DGEN ready" only. This solves the question of non-stock objects, puts the bar of PC performance quite high as well as the level of computer literacy required by future map users.
Alla prossima!