Ok, well his special attack and attack are only 5 points away from eachother, so you could go with either. It just depends on what moves you want to use (special or regular), then get a nature that ups one and downs the other.
As for moves, to combat a fighting poke (that lucario is weak to) you'll want a psychic type move.
If you went the 'physical attacker' route, you could have it learn Ice Punch to combat the ground types that are also a weakness.
Drain punch is a fighting attack move that heals you, so it's always handy.
Focus blast would dish out some mighty damage, though it's a special attack.
as for status effecting moves....
Bulk Up - to increase attack and defense Swords Dance - increases attack Calm Mind - good for increasing the damage of your special attacks.
Play around with some of these and you'll probably find something that works for you.