Hi,
LECU has currently undergone great improvements in the airport and it's surroundings. They have built a new tower and the terminal building has increased capacity. I do warn you however that this is a vfr airport with little or now radioaids, it has a PAPI which is no working half the time, and a very short RWY, I don't remeber exact lenght. As guatico said it is half military, but mostly used by flight schools. I have only seen 1 jet land there, and this is a military citation that does ILS precisioning for barajas and torrejon.
I really don't think it could seriously have the capacity for any airline, unless you are thinking of using a small turbo prop, say a C-90 or similar.
Torrejon, takes on heavier jets, and has all the corporate aviation that doesn't go into Barajas. You can see anything from senecas to G-V. This airport is also close to madrid, maybe a 40 min. drive to Madrid centre.
I would look into Valladolid airport, with more facilities and infrastructure, onlt thing is that it is more or less and 1.15-1.30 drive from Madrid.
Hope I was able to help.
richiya