Orion is perfect for typical pug matches--at open you hang back and fire long-range weapons on the enemy to soften them up and/or make them move out of their dug-in positions, then you walk in and mop up whatever is left at your discretion. It's not for going sniper-v-sniper or missile-v-missile, it's for digging them out and killing them on your own terms. Nor is it for going toe-to-toe against a lance of undamaged assault mechs, it's for breaking them down and then coring them out when they are exposed. In that regard, Orion will spoil you with the full-game potential, while most other mechs feel like they are stuck to specific roles.
You also need to play to the strength. Its not a sniper mech for peeking over hills. Instead set your right arm to an individual weapon group, turn your torso sideways, and peek from around the side of a structure, then dump your right laser+ballistic while backtracking into cover. Meanwhile the high position and angle of the missile hard-point lets you use indirect fire over buildings and berms easily if you managed to lock target. After a couple minutes of that, the enemy will definitely seek better opportunities elsewhere. Then you go in close-combat mode, activate the weapon group with both arms enabled and beat them down with high energy damage while still using your ballistic and missile hard-points, while they are in unfavored position. The arms unlock for high range of motion, so you can keep engaged if the target jumps above/below your torso. And you can use the arms for torso shielding as well. Very few mechs have this kind of setup.
I have a K and a V that I change around depending on how many ballistics I want to mount at a given time (I also bought an -M but I found it redundant so I sold it after leveling).
ON1-V All-Range does optimal damage in the 200-600m range but is +60% effective inside and outside of that, and all weapons can reach targets up to 1k distance effectively.
As a different build,
ON1-K Close Support gives up the torpedo for additional energy weapons, which makes it more effective for close-range combat at the expense of being able to spam out LRMs. Optimal damage is in the 0-400m range but it can go beyond that if needed (up to 1k, but poorly). You can also slot an XL360 with 4 internal heatsinks on this build and be very mobile, can switch the MLs for SRMs, etc.
Overall they are very enjoyable, solid performers.
edited for mass typos and clumsy thoughts
Edited by UrsusMorologus, 16 September 2014 - 10:46 AM.