Questions #1: Any idea why the My Google Maps located those lighthouses inland?
It is probably due to the the lighthouses not having any street address. Many lighthouses do not have formal addresses.

Question #2: What do you think are the advantages of including pictures or additional information on a web map?

It aids readers to understand your point of view or concept.

My map is to show where my partner and I like to go. This includes our favorite places to eat, explore and drive.

Pros of My Google Maps: Easy to use and set up. It has easy features to find.

Cons of My Google Maps: Certain features do not work as intended, such as “draw my route”. Embedding also was tricky and seemed to not work as intended.

<iframe src="https://www.google.com/maps/d/embed?mid=1_Why_PN_Gdc9FT7_jTtJze39I2Rs6mYz" width="640" height="480"></iframe>

https://www.google.com/maps/d/edit?mid=1_Why_PN_Gdc9FT7_jTtJze39I2Rs6mYz&usp=sharing

https://www.google.com/maps/d/embed?mid=1_Why_PN_Gdc9FT7_jTtJze39I2Rs6mYz