Everyone else probably knows this but I realized last night:
Misty Step- BONUS ACTION- ONLY VERBAL- Hello, getting out of a grapple! or CHARGE!
Fly- speed becomes 60'- Yeah, my dwarven warlock is now faster than the monk with wood elf monk with mobile!
The Moonbeam spell is particularly nasty against hordes of low-level enemies like kobolds. Assuming average damage (11 at 2d10), it kills a normal kobold even if it saves, AND you can move it up to 60 feet on your turn-- and it only uses a 2nd-level slot. Combine that with its 10-foot diameter and you can use it as a very effective tool to make choke points as well. Bearing in mind it deals radiant damage, which almost nothing resists or is immune to, I can see it as a great spell to use at almost any level.
I don't cast the spell through the familiar, I cast the spell in person, then use the familiar as a long distance remote control.Mephista, I too play a GOO Chain Warlock and have had a lot of fun with invisible flying shapechanging familiars (usually a Quasit). However, the miles-away Suggestion trick doesn't work RAW.
Yes, you can see out of your familiar's eyes and thereby satisfy the "a creature you can see" requirement for targeting Suggestion. But the range is still 30 feet. 30 feet from the caster. That's you.
Heroes' Feast is fantastic, and actually a better thing to spend a spell slot on than Heal. It makes 12 people immune to poison, immune to fear, and gives them advantage on all Wisdom saves for a day. I found this out after I created a dungeon of creatures that relied on poison, fear and charming. The group is chortling every single time the spell helps them out. They're chortling a lot.