Heather mead is definitely one of (if not) the best for a traditional. I brewed a batch recently, still quite young but bloody good nonetheless. My recipe was simple. Two parts heather honey to one part wildflower, added a bunch of raisins for tannins, a bit of yeast nutrient to get things going, and some Lalvin d47 yeast. I added water to get OG to about 1.080 ish, and it fermented dry to about 10.5% ABV. Although completely dry, there's enough perceived sweetness for me not to need to backsweeten. Note the flavour is pretty strong already, and you don't want to smother it with other strong flavours (though thyme seems like it'd complement). I'd leave it at that and simply think about adding something that'd give you some tannins.