1. Teamwork is more important than anything else.

2. Teamwork is more important than any other thing.

3. Teamwork is more important than all the other things.

4. Nothing is more important than teamwork.

5. Nothing is so/as important as teamwork.

6. Nothing else is more important than teamwork.

7. Teamwork is the most important thing (of all).

(Are all the same expressions? Do you have other similar expressions. Do I have to use 'of all' in #7?)

#2 is awkward.... Other than that, you may use all the other sentences.

On 5 "as" is preferable to "so".
No, you do not need "of all" on 7.

All the expressions you provided convey a similar meaning that emphasizes the importance of teamwork. However, there are subtle differences in wording and tone. Let's break them down:

1. Teamwork is more important than anything else.
This expression makes a definitive statement that teamwork is the most important aspect, leaving no room for comparison or alternatives.

2. Teamwork is more important than any other thing.
Similar to the first expression, this statement emphasizes the superiority of teamwork over any other aspect, indicating that it surpasses all other things.

3. Teamwork is more important than all the other things.
This phrase also highlights the significance of teamwork, but specifically mentions "all the other things." It suggests that teamwork surpasses every other aspect or factor being considered.

4. Nothing is more important than teamwork.
This expression conveys the idea that there is nothing that holds greater importance than teamwork. It emphasizes the unique value of teamwork above all else.

5. Nothing is so/as important as teamwork.
This statement uses a comparative approach, highlighting that there is nothing that reaches an equal level of importance to teamwork. It implies that teamwork stands as the top priority.

6. Nothing else is more important than teamwork.
Similar to the previous expression, this phrase specifically mentions "nothing else," reinforcing the idea that there is no alternative or substitute that can outweigh the importance of teamwork.

7. Teamwork is the most important thing (of all).
This expression emphasizes that teamwork holds the highest level of importance. The inclusion of "of all" strengthens the statement by implying that among all other things, teamwork stands out as the most crucial.

Regarding the use of "of all" in #7, it is optional and can be included to further emphasize the significance of teamwork above everything else. However, even without it, the expression effectively conveys the intended meaning.