As you have correctly understood, し after the dictionary form of a copula/verb/i-adjective is usually used to connect two clauses. The first part often works as the reason of the second part. In English it's like "and" or "so", depending on the context.
If a sentence ends with し, it's either one of the following:
The "consequence" part is omitted because it can be inferred. It's like ending a sentence with "so".
But I'm Maggie, so...
The following part is something like "don't call me like that", but it's left unsaid.
It works as the reason for the previous statement. In this case it's like "(it's) because ...", "coz ...", "I mean" or "you know".
見てよ、面白いし！ Watch it, (because) it's fun!
帰ろう。もう夜だし。 Let's go home. (Because) It's night.
If you are a beginner, you can stop reading here.
Your sixth example is different from the other five. #6 does not sound particularly weird to me, but し after the imperative form of a verb is recent nerdy slang mainly used on the net. (It's originally a dialectal particle, but it somehow became a nationwide slang expression in the last 20 years or so.) This し emphasizes the imperative, like "hey", "yo" or "come on". This usage is not in a serious dictionary, and you should not use this unless you really understand how it sounds.
- ゆっくりしてけし。 Make yourself at home. (slangy)
- 嘘言うなし。 Don't tell a lie. (slangy)