Ferrydds: It would help to have a better idea of what your expectations are in a zoom lens.
Is there a camera system you are comparing it to that gives you the size range you are looking for?
Is the 18-55 too big for your taste, ferrydds? It is something like 330grams for a fairly fast and very high quality zoom with optical stabilization.
Were you looking for something smaller than that? If so, the XC 16-50 is only around 195grams and 6 1/2 cm in length and width (not a lot shorter but 130 grams lighter). Hard to beat that. Not quite as good or fast but certainly lighter and cheaper. It isn't likely to get much smaller than that. And 16 is pretty wide for consumer grade glass. (24mm in full frame is very wide).
Maybe you are interested in longer than 55mm or shorter than 16mm zooms?
Going wider than that increases the design challenge and the customer expectations for quality. Your typical entry level consumer doesn't want a wider lens and those who do are likely to be serious amateurs or pros, and will expect higher quality which, for a zoom in the ultra wide range requires a lot more engineering. An f4 zoom like the 10-24 with autofocus and stabilization would be hard to make smaller without making it slower (very few would buy that and autofocus would become much harder to use in a lot of conditions).
Going longer, the lens has to get longer and if it gets longer, it has to get wider to let in the same amount of light. The longer XC 50-230 zoom is again pretty small for the focal length in an autofocus design (about 11cm long by 7 wide). Hard to beat that.
Longer than 230 again puts you in territory where fewer want it and those who do will have high expectations for quality.
