Just created three more (and changed one):

grid Changed to 1px border
thick_grid New class with the 3px border
thick_outer_border New class with 3px outer border and no inside borders
thick_outer_border_grid New class with 3px outer border and 1px inside borders

Examples:

thick_grid
[table="width: 500, class: thick_grid"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111


thick_outer_border
[table="width: 500, class: thick_outer_border"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111


thick_outer_border_grid
[table="width: 500, class: thick_outer_border_grid"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111


Header with both alternating row colours and thick borders
[table="width: 500, class: head alt1 alt2 thick_grid"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111


Header with both alternating row colours and thick outer border with no inside borders
[table="width: 500, class: head alt1 alt2 thick_outer_border"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111


Header with both alternating row colours and thick outer border with thin inside borders
[table="width: 500, class: head alt1 alt2 thick_outer_border_grid"]

Spoiler
Show
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111
111111 111111