when adding new addributes, Option Value sorted?

[Ajeh]

You can setup on the Option Values the default sort order and then apply it after adding the attributes ...

There is also the Option Name Sorter and Option Value Sorter to help you sort existing Option Names and Option Values ...

I usually use sort orders number by 10s but in the case of values of measurement I would use something related such as:
70
75
80
85

If you want to group the colors you can do that as well
1075 where 10 is gold and 75 is 7,5
1080 where 10 is gold and 80 is 8,0
2070 where 20 is silver
3075 where 30 is steel grey

These allow you to get creative in your number methods ...