Close Mic Sound Characteristics
The sound of orchestral instruments is heavily influenced by the room it plays in. With some instruments, the interaction with the room is essential. For instance the French Horns which always project to the back of the room and bounce off the back walls into the audience (microphones). Placing a microphone right at the bell of the Horns would create a very unusual buzzy sound.
Therefore in order to get the typical orchestral soundtrack sound, you should rely quite heavily on signals by microphones that are more distant from the instruments. The problem with signals that are recorded very close to the instruments is that you get a lot of close mic noises which decrease a lot over a just a small distance (e.g. air noise on brass/woodwind, bow scratching noises on strings). The close mics are great for ADDING a bit of precision and definition or getting a very intimate sound. However if you want an orchestral sound, the microphones further away from the players (e.g. Decca Tree signal) should be your base.
There are quite a few sample libraries on the market that come with different (sometimes extensive) microphone options that allow you to shape your desired sound. However a few companies also still offer only very close miced samples, sometimes even recorded in an anechoic chamber. The argument for that is to be completely flexible with the choice of reverb you want to add. While this is true to some extent, it is not possible to reduce the typical close mic sounds mentioned above just with reverb. The processed signal will still sound like a close mic, just with more reverb. On the other hand, relying too much on more ambient mic signals might build up mud and lose precision, so try finding a balance.
As a side note I can only encourage to experiment with different mic options your sample libraries offer as the sound can be shaped quite dramatically with just balancing these. This should be the first step before you try to solve problems with EQ or reverb as it will maintain the natural sound. Of course this will put more strain on your system (except for a new recently developed technique by one developer that allows to merge your mic mix into a new single signal basically saving your personal mix into a new single mic position).