OP can make a thread about whatever they want. Also since the vast majority of people who seem to disagree never explain or support their position with anything substantial, I don't see why their answers should determine the validity of such a topic's existence.
1. Okay, so we can all agree that John and Kelly love each other. That's good. However, the exact nature of that love is then subject to personal interpretation. If you see it as being strictly platonic, that's totally fine. There's nothing in canon that says otherwise. But there is also nothing in canon that says the inklings of romantic interest between them aren't there either or never could be. And at least we do know for a fact that romance between Spartan-IIs was definitely something that can and did happen.
2. Nothing was "misinterpreted" though - everything stated still has a basis in canon fact. Now if your own interpretation of the events and issues varies, that's fine. But what OP referenced wasn't wrong. Every time in Halo canon where we have seen John pick his team he has always chosen Kelly as a teammate, save for that one time during the siege of Reach. And yes, in the book John does say what skills James and Linda posses that he considers an asset to the space op; but the fact that he also says that he was certain the ground op was the safer mission combined with the fact he's not taking his regular Blue-Two with him (in spite of the fact she openly volunteered to go) is still something that seems notable. Aside from that we simply don't have enough details about the other missions the Chief went on that somehow garnered him more campaign/mission credits than the other S-IIs (though interestingly enough Kelly is second in number of missions/campaigns, so it's still not unreasonable to assume she was with him for the majority of them). Like Kelly, was he selected for a number of solo operations? Where there also times where he didn't get to personally pick the squad he worked with? We just don't know. Nobody here is saying that Kelly "never left the Chief's side ever", just that based on what we do know it's pretty clear that she's definitely been his most consistent companion. And that means a lot no matter how you see the nature of their relationship.
3. Again, nobody here is saying that the Chief wouldn't protect any of the other Spartans if they were wounded and in danger. Just that that moment in 'First Strike' definitely adds to the count of times where the depth of John and Kelly's bond has been highlighted in the EU, which is more than any other pair of Spartan-IIs. So make of that what you will - be it platonic, romantic, or something in between.
4. While fraternization between trainees is certainly not allowed during boot camp, it should be noted that Chief Mendez does not separate Black Team after Margaret and Otto are ratted out by Victor. Which doesn't make much sense if he was serious about discouraging further relationships from cropping up. Also as far as Red Team is concerned, it is elaborated on by Otto in the comic that they only attacked Black Team while they were in the brig because they were mad about having been thoroughly trounced by Black Team in a training exercise earlier and Red Team was just using Otto and Margaret being caught as an excuse to start a fight. So really the only reason Otto and Margaret's relationship was undone was because Victor was jealous of them since he was in love with Margaret too - but even after this falling out Black Team was still able to maintain unit cohesion and worked effectively in the field together right up to their untimely demise in spite of the fact Victor's romantic feelings for Margaret never fully went away. John and Kelly do not have this issue however, so it stands to reason that they would be more than capable of harboring romantic feelings for each other and still be perfectly fine being on a team together and able to do their jobs without fail. And for them to enter into a relationship in the future would not be out of character for either of them given the right circumstances.
5. Once more, this is basically of a matter of interpretation. Though it's already been outlined how what we currently have to work with could definitely be used as the basis for a romance to be built/confirmed later on - so it wouldn't be "out of nowhere" by any means. And again, nobody here is asking for anything more than the same type of subtle gestures they've displayed in the books. Also how would it be "butchering their established characters" to have two best friends who have always respected, supported, and cared for each other in healthy ways finally find some peace together after their work is done? Like I've said before as well, logically speaking it's unlikely to happen, but there certainly wouldn't be any harm caused by it if it did. That's essentially the point OP and others like myself are trying to make.