Rotom actually looks like a pretty nice lead in a lot of ways: you're immune to fake out, outspeed most leads, and your two stabs offer great coverage on leads like kabutops/omastar/moltres/uxie/mespirit/etc. HP fighting rounds out coverage, hitting ambipom most notably, and then you're left with really two options for your last move in my opinion: sub or sucker punch.
Substitute would be timid with life orb and would really be used to dodge status/sucker punch, scout, and set up on predicted switches.
Sucker punch should be run with naive nature and a focus sash: after bringing them down to low HP with shadow ball, tbolt, or hp fighting, sucker punch kills them, letting you beat most focus sash leads quite nicely, e.g. Alakazam, sash ambipom, etc. You can also dodge sucker punches by using it (doing laughable damage, but you can waste some pp or potentially out mindgame an absol or somesuch) or get in a last (weak) hit against a scarfer.
There may be some other nice options: hp ice or grass over hp fighting would potentially help with ground and rock type leads, although shadow ball or hp fighting do quite a bit and beating ambipom is one of the major advantages of a ghost lead. Wisp could potentially be used to cripple spiritomb but is otherwise pretty terrible. I've just been using 252/252 spreads, but others might be alright too.
All in all, rotom makes a solid anti-lead, capable of preventing hazards from going up, countering many other anti-leads, and establishing an early offensive presence that is hard to set up on.
Substitute would be timid with life orb and would really be used to dodge status/sucker punch, scout, and set up on predicted switches.
Sucker punch should be run with naive nature and a focus sash: after bringing them down to low HP with shadow ball, tbolt, or hp fighting, sucker punch kills them, letting you beat most focus sash leads quite nicely, e.g. Alakazam, sash ambipom, etc. You can also dodge sucker punches by using it (doing laughable damage, but you can waste some pp or potentially out mindgame an absol or somesuch) or get in a last (weak) hit against a scarfer.
There may be some other nice options: hp ice or grass over hp fighting would potentially help with ground and rock type leads, although shadow ball or hp fighting do quite a bit and beating ambipom is one of the major advantages of a ghost lead. Wisp could potentially be used to cripple spiritomb but is otherwise pretty terrible. I've just been using 252/252 spreads, but others might be alright too.
All in all, rotom makes a solid anti-lead, capable of preventing hazards from going up, countering many other anti-leads, and establishing an early offensive presence that is hard to set up on.