Well the way I think oculus should be played is by using the passive lightning end game. Early on 5% isn't good but at level 14 which is normally when I max it in addition to almost full creep waves and my own 6 minions 10% for 100 damage is a sizable increase of DPS if you look at it. Saying a full minion wave may activate it once a second thats 100 extra damage plus if you are near other generals and plus your own minions it can easily add 200 dps on it's own.
I find his stats increase from minions very useful. The minotaur health has actually saved me. Summon minotaurs to buy time to warp away with blast off.
A very passive build I saw as not very useful but if ball lightning was buffed and with it's fast attack speed 4 ball lightnings make that 10% even more effective.
Blast off is one of the most useful skills on oculus. I couple it with cloak of night and in one game got 3 kills when a fellow DA only got 4. Amazing chaser and coupled with chain lightning adds even more DPS.
In my mind oculus isn't a nuker and is horrible at single targt damage. Basically my stategy is kite them while my maxed out minions hack away. And if creep waves are involved take out those creeps and let those bash away at the enemy demigod as well. When the enemy gets low on health then I do chain lightning blast off cloak of night and chain lightning again and normally they will die. Plus oculus is a VERY good person at taking down towers. Chain lightning can snipe a creep wave just as it rounds a tower to kill everything in the wave and damage the tower too. Which afterwards just send in your minions and whatever creep wave is coming up behind you and auto attack that tower down.
Although I think that his ability that gives him stats from his minions should give his minions extra stats too.