If Ash is going to get a new dragon type to replace Goodra, I hope it's either Tyrantrum or Dragalge. Perhaps he might not get another dragon type, but it does leave room for another Pokemon, I would like it to be a Pokemon who has a typing which Ash doesn't have a Pokemon of, such as steel, ghost, psychic, or fairy. Honedge and its evolution line would kill two birds with one stone.
The problem with the Skrelp and Tyrunt lines is that the former would not really suit non-aquatic conditions (remember that Misty's Goldeen always like flopped around on land which I think was the excuse for why it had such few appearances) and fossil Pokemon seem to always never make it onto the main cast for some reason.
Honedge is something I've heard people wanting him to get, but I want him to eventually get his Grass-type. Hopefully a Phantump, because that could give him his first Ghost-type as well.