I found a neat bonus move for scarab 21 that is not on your list: If your totals form a straight (eg 17,18,19,20,21) you will get 100 points and all columns will be cleared!

 

If each of the rows has a sum (other than 0) that is equal to all the other rows then you get 250 points and the rows are cleared. I've only done that once since it's really hard to get the rows to equal each other, but it is possible.

 

2 kings in a row -- 100 points and clears all rows
63363 combo -- 200 pts

three 5's and two 3's --200 pts
5 of a kind -- 100 pts
20,19,18,17,16 -- 100 pts
jack and ace of spades -- 50 pts
2 blackjacks in a row -- 50 pts