I'd rather have a starter pack than jump leads. They would have to be pretty long to help out another boat where as the pack can be taken pretty much anywhere.
Remember that it is a sailboat, and that for centuries boats came in using the wind. And certainly, don't consider the engine to be your heavy weather plan.
Sail as close to the harbor as you can.
Consider an alternate harbor. Sometimes that is the best plan.
Practice short tacking. You should be able to manage most channels.
You may have to wait for the wind or tide to change. You may have to anchor overnight. This is the sea, not the freeway.
Kedging. If you don't have far to go, row out an anchor, haul, and repeat. Lots of rope helps. It goes faster than you think.
Tow with dinghy. Kayaks are particularly good for this. So are small motors for the dinghy.
Get a tow. There are lots of good Samaritans, so long as you are not aground.
If you are trying to fix the motor, but might drift into trouble, anchor first!!! Sail somewhere you can anchor, if you must. That stops the clock, so that you can think. Too many boats have run aground because the motor wouldn't start, and it never occured to them to anchor. They just didn't think of it.