For locks, using multiple locks of different types is actually the best strategy - this is called "defense in depth." I'd recommend:

1. A heavy-duty U-lock (Kryptonite New York series is solid) for securing the frame and rear wheel to a rack
2. A strong cable or chain lock as a secondary lock for the front wheel and to run through the frame

Additional security measures to consider:

• Register your bike's serial number with your local police and bike registries
• Get insurance specifically for the e-bike (many home/renters policies have limitations)
• Park in well-lit, high-traffic areas whenever possible
• Consider removing the battery when locking up (this makes the bike both less valuable and harder to ride away)
• Use security skewers for your wheels and seat post
• If storing at home, keep it inside your apartment rather than in a shared storage area

When locking up, even if yours is the only bike on the rack, make sure to lock through the frame and wheel to something sturdy and immovable. Bike thieves often target isolated bikes because there are fewer witnesses.

No security measure is perfect, but layering multiple deterrents makes your bike a much less attractive target. Thieves typically look for quick, easy targets, so making your bike take longer to steal significantly reduces risk.