Oh hell yess. The problem I have always had with Johnlock is that a vast majority of the shippers oversexualized it constantly and that always pissed me off. But because of recent things happening, as well as what we've seen of John and Sherlock's relationships and canonical info, the two having a QPR is the most logical and my favorite outcome. Sadly, most of the fandom obsessively ships them romantically and sexually so there's no real way of getting the idea of a QPR through to them.
A few aro/ace headcanons that I have are Jake English and Tavros Nitram from Homestuck.
Warning: SPOILERS (probably)
Jake English: Part of Jake's character arc is his discomfort and unhappiness due to the romantic advances directed at him by two of his friends and by one acquaintance. Though he intends to be the suave and romantic hero of his dreams who woos everyone he meets, most specifically blue alien girls, Jake ends up overwhelmed and even in tears throughout all the romantic situations he encounters, traits which highly hint towards him being aromantic.
Tavros Nitram: In Tavros's few romantic encounters, he always reacts with extreme discomfort. First we'll start with his relationship with Vriska Serket. During the trolls' game session, Tavros crashes into Vriska's hive to find Vriska wearing a mildly suggestive fairy costume, a nod to Tavros's love of Pupa Pan. Vriska grabs Tavros and kisses him, attempting to manipulate him with her mind powers to start a relationship, but giving up and then regretting her advances later. Tavros is urged by Heart Boxcars to kiss her back, but Tavros chooses not to as he does not want to kiss her. Vriska then apologizes to Tavros and the game session continues. Later in the story, Tavros then faces the advances of Gamzee Makara, who for the longest time was his closest bro. Gamzee hints to Tavros that he wants to make out with him and Tavros simply responds with a whole lot of ",,,,,,,,,,,,,," notifying the audience of Tavros's discomfort at the thought of kissing his best bro. Then more shenanigans happen and we all know how Tavros ends up.......
So wwwwooooooo headcanons.