I'm not sure what you mean by scale, either LTSCALE, DIMSCALE and the line's Linetype scale property.
But for what it's worth, here's what I do.
I leave the entity's Linetype scale property set at 1.0, unless it's linetype is BATTING.
In Model space, I set DIMSCALE to the DWG's required scale, like 96 for 1/8"=1'-0" scale. (This can change if I use different scales within a DWG.)
I set LTSCALE at 1/2 of DIMSCALE.
If a non-continuous linetype doesn't display at these settings, I alter the entity's linetype to another size of the same basic linetype: CENTER to CENTER2 (or going the other way: CENTER to CENTERX2).
CENTER2 comes with LT, but you can create CENTER4, CENTER8... by copying CENTER2's linetype definition and halving its values.
Double CENTERX2's values to create CENTERX4.
You get the idea, I'm sure.
In Paper space, like in Model space, LTSCALE is 1/2 of DIMSCALE. But since Paper space is a 1:1 arena, LTSCALE is always 0.5 (1/2 of 1).
Bonus freebies!
Here's a macro to do these LTSCALE computations depending on DIMSCALE and TILEMODE.
This is written to be added to a pulldown menu. The current LTSCALE is displayed on the menu.
^C^C_setvar;ltscale;$M=$(if,$(eq,$(getvar,tilemode),0),0.5,$M=$(/,$(getvar,DIMSCALE),2.0)) REGENALL;
Here's the same thing, but just displays DIMSCALE.
$(getvar,DIMSCALE): DIMSCALE
One last macro.
Assign this macro to a keyboard combo (I use Ctrl+T) and it toggles you between Model and Paper space, setting LTSCALE as described above.
^C^C_setvar;TILEMODE;$M=$(if,$(eq,$(getvar,TILEMODE),0),1,0);_setvar;ltscale;$M=$(if,$(eq,$(getvar,tilemode),1),0.5,$M=$(/,$(getvar,DIMSCALE),2.0)) REGENALL;$M=$(if,$(eq,$(getvar,tilemode),0),^C,ZOOM;E;ZOOM 0.95X)
I hope this helps.