I’m also hoping for a new Zelda rep although I think Tetra and Tingle aren’t really a part of the competition (at least not from what I’ve read from reddit, fb, gamefaqs) I think the newcomer is speculated to be Skull Kid while a possible echo would be Impa or Hilda.
Tingle I generally agree with, although I strongly disagree about Tetra. Sakurai's already tried to include her in Smash (most likely) once already. She's one of the better known Zelda characters in Japan, one of the most recurring characters in Zelda - considering she's a single character from one era of Zelda that came back three separate times after Wind Waker, which is A LOT for any individual Zelda character - and had a lot of attention leading up to the fighter ballot in '15. She lead the advertising campaign in Hyrule Legends, enjoying renewed popularity with Wind Waker HD not long before that, and (although she didn't personally appear in it), probably also enjoyed some help from another Toon Zelda game - Triforce Heroes - which was released just months before the ballot began (interestingly, Triforce Heroes was originally supposed to be a sequel to Link Between Worlds, but reverted back to Toon Zelda style because it's so popular). Toon LoZ's continuing popularity was also evidenced in Pirate Ship (Tetra's own ship), being the only non-64/non-newcomer stage introduced via DLC aside from Mario Maker and Miiverse, and the only major Zelda-themed content we received via DLC for WiiU Smash Bros., apart from Link cap and Majora's Mask costumes. Which may be a clue as to how well Toon Zelda/Tetra did in Sakurai's unseen polls. Tetra is also a leading star in Aonuma's own favorite Zelda game: Phantom Hourglass - which incidentally started receiving strange representation of its own starting in WiiU with Zelda's new down-B Phantom Slash attack. Also of note, Toon Link's home stage for Ultimate was set for Spirit Train - a game he did not originate from and is not most well known by - while Tetra's Pirate Ship stage (popular enough to come back for DLC), remains currently unaffiliated.
This is all aside from the fact that Tetra herself one of the most expressive, developed, unique characters in Zelda lore, and an honest to goodness pirate (which Smash utterly lacks). Her addition would balance out the aesthetic of the Zelda roster well, which looks a little serious and Fire Emblem-y right now, while Toon Link sticks out like a sore thumb - which I don't think fully appreciates the Zelda series' wide range of settings and tones. Given that Toon Zelda's already strongly represented in stages, and Sakurai evidently wanted to create the character at one point - it seems profoundly evident Tetra would be a natural character to consider.
Honestly, it seems the only reason people are against her is because they dislike the idea of having three Zeldas. Which is a fair point, although Tetra looks, acts, and her entire moveset would be so utterly unlike Zelda (given she doesn't even let people call her Zelda, she's practically an entirely separate character already - an anti-Zelda; she wields a flintlock pistol for goodness sake), the point appears very strained to me. It’s likely she doesn’t even have the Triforce for her appearances outside of Wind Waker (where she lost it). Regarding Impa: I do really want Impa to be on the roster - she's definitely earned a spot - but I don't think she adds nearly as much to Zelda's representation as Tetra would (what other franchise could boast introducing both a ninja AND a pirate?), and her strongest argument for inclusion seems to be that she's had such a recurring role - a role Tetra has four times the exposure of for any single iteration. Had they both been one-offs, I have doubts as to whether Impa would be a viable contender, whereas Tetra would likely still have a strong following (if one-offs like Midna are any indication). Not to mention, we've already got a few ninja characters - that's been done - Impa doesn't fulfill any vacant niches that I can see. Given Tetra's unique look, moveset options, relative popularity, and coveted role being one of Sakurai's chosen, scrapped characters (who have a habit of getting in later, if Dedede, Marth, Mewtwo, Ridley, etc, are any indications) - I think ruling out Tetra is simply silly. By Sakurai's own considerations, that she deserves a spot in the Smash Bros roster is hard to deny.
EDIT: I want to amend one point made here, after Legendary Spirit Tamer informed me of a few things. Sakurai considering Tetra for Brawl comes from datamined information containing files named for Toon Zelda and Toon Sheik. While these may be placeholder names, we this is difficult to verify, as most characters use their literal names for their files. We do have instances of Sakurai using nonspecific names for character files, such as Melee's use of the title "Fireemblem" for Roy. Considering "Toon Zelda" would have been a clone of an already existing character (given they area a clone of a transforming character, this is a unique situation) who was still at a conceptual stage, it's hard to say whether "Toon Sheik" was supposed to be a literal reference for her or not. At the very least, I think it likely Sakurai would have eventually changed this character to Tetra anyway if that was not already the plan, as Tetra had been polling very well (and based on all the data I can find, far better than Toon Zelda, who I can find no polling references to) - and it was clear this general character was on his radar. However, it is important to clarify that there is currently no concrete proof to point to that Tetra was planned for Brawl. Thanks Legendary Spirit Tamer!
https://smashboards.com/threads/characters-on-sakurais-poll.71872/