First of all - hi! I'm really excited to be receiving a gift in this exchange from you. To make things rather short, let me tell you that I will be absolutely happy with anything you create for me; what matters the most is that you are happy and comfortable with your piece. I, however, am a complete sucker for anything dark-ish, mysterious and particularly angsty (angst is my crack while pure fluff is not something I usually read).
Generally I'm pretty open for anything, just please try to stay away from heavy graphic torture (including mutiliation and overly gory descriptions), PWP stuff (I am generally not a huge lover of smut fic/art, so if you choose to stay away from it completely, that's fine with me!) m-preg, kinks such as watersports/scat, crossovers in general and extreme AUs (a good example for that would be modern!AU in the ASOIAF fandom which doesn't really apply for this exchange but should give an idea of what I mean). Otherwise, anything else is game!
One of my true OTPs in Harry Potter, based solely on my own headcanon of course, are Druella and Cygnus Black, parents of Bellatrix, Andromeda and Narcissa. As I said, I want you to be comfortable with writing or creating, so I will not push you into a certain direction by sharing my whole headcanon with you (which would also take too long), but I will simply tell you that in my eyes they love and have always loved each other fiercely and share a deep connection to one another. If you have your own headcanon about them - go with it! I'm excited to see what you do if you choose to write me Druella/Cygnus. Just please please please refrain from one thing: I've seen many fics that portray Cygnus as an abusive and rather cruel husband and father, which... No. Just very, very much no to that. In case you are an artist who chooses to draw them for me - my dreamcasts are Sean Bean and Rachel Weisz, but if you prefer to show me how you think they look like... Go ahead!
While my second big and intense OTP are Lucius/Narcissa - who unfortunately are too popular for this exchange - I actually also ship the Black sisters amongst each other; I've always seen it as an incredibly intense sisterly love that sometimes (especially when Bellatrix is involved who I tend to believe pushes her sisters beyond a line they usually wouldn't cross) drifts into... more in case that makes sense. Again, do whatever you like to do with them!
The Mummy Series
One pairing I have come to ship fiercely, forgotten about for a while and re-discovered with doubled intensity, are Evelyn and Rick O'Connell. My full OTP feels only blossomed during The Mummy Returns, which I also far prefer to the first (while the third does not exist in my head), so if your piece could take place around the time of the second movie, that would be fantastic! An Evy!centric fic would be awesome, because I am so in love with that woman, haha. Generally, though, I don't have much headcanon yet for them to share, so I am completely excited and curious to see what you do with them!
From the beginning on, Mrs Danvers has been my favourite character of the book and every adaptation I know (BBC mini series which is my favourite, Hitchcock movie and the German musical), and the further I got into reading the more I started to ship her with Rebecca de Winter. I think Danny is a true tragic character; she loved Rebecca fiercely (whether with truly romantic ambitions or not is unknown but I tend to lean towards yes) and does not see until the end that she, too, was and still is a victim of her Mistress' abuse just like any other man. I think their dynamics together are an incredibly fascinating thing to explore - whether from Rebecca's POV or Danny's - and whatever you choose to do with them, it's going to be fantastic.
Again, though, I want you to be happy with what you create - you are the author/artist, and you decide what to do. What matters the most is that you enjoy writing or drawing. I really cannot wait to see what you come up with! ♥