They would both be incredible additions, honestly.
But strategically....
If going non-stim: LX+DCP=King
If stims are considered, HEAT+a stim source is really wonderful, and I am a huge fan.
Really depends on what kind of sensation you prefer. DCP and LX won't yield any physical feeling, per say (some users report increased thirst, etc). HEAT will certainly turn up the temperature on you, especially when combined with stims. Both are amazing, and both would be amazing stacks. I'd say stack all 3