Further interaction with Cove, along with (a little) extra content with your family and friends.
Despite the game being fun and free without the DLCs, I believe them to be pretty essential to developing Cover's personality to a more satisfactory result; because, when I first played the game straight through, choosing honest choices to fit my personality, without the DLCs, my Cove grew up to be pretty annoying/emo (a negative for me), but picking the same options again with the DLCs added, actually gave me a personality I enjoyed (and made a lot more sense for someone like me), and I generally picked the same options.
To be honest, though, I got better results when I started
grooming 
Cove by picking answers I guessed at what would influence him; I can't say exactly what makes Cove grow into who he is, but from my experience, I would guess the writers were going for a more "Opposites Attract" approach, as the more I played a shy/quiet character, the more "dominant"/open Cove becomes, which was a huge conundrum coming from a Dom like me attracted to other Doms. (I'm leaning heavily on this "Dom" word, kinksters, but I really mean "extroverted/blunt")
Hey, look, I hear you, I'm not going to be cute and say sappy men is a turn on (but honestly, be less harsh! Like, let men cry, and feel, and hug your sons, please! The more we stifle masculine emotions, the more we get 'roid-rage Dude-Bros that thinks it's okay to stink up society). But I hear you, the whining does seem to be played up as a token...
something? Woke-ness? "Sensitive masculinity"? I honestly don't like Cove's gloomier personalities, myself, but I managed to cultivate a route that made his tears rather reasonable...? (I don't think 18 year old Cove
unreasonably cries much, outside of the "sappy" love moments? Which only happens... twice, I think?)
I say reasonable, because I get why he would cry, so it didn't bother me, but I only played this game with a dating focus, so I don't know how he acts if you go the friend/hate routes??? Plus I figure if you pick the more sappier options, you kind of get what you get if you giving, Nah'mean? (I picked a lot of sappy options, and got sappy results) Without his love for you, I guess the tears can feel kind of silly if he's crying still???
Now, you were pretty snarky in your comment, so I don't know if that intensity was for the laughs, or if you're the type that don't think men should cry (a bit archaic, and highly toxic, but, hey, you're fitting into conservative society with all your tittles dotted!), but if you're okay with men being human (or Homeric heroes, if that makes it feel more masculine), then you might want to follow my tips above, if you want a more outspoken, maybe even a bit snarky Cove (I may be exaggerating it a bit, but this last play through was a lot more tolerable when I got him to be the conversation starter (I'm usually the one saying/initiating/encouraging things; that was making Cove the lessor voice in a lot of events!).
I'm a little confused with the personality adjuster, I tend to let my actions shape Cove, so I don't know what I balanced him to (I think he was set on Cold/Sporty when I went to check), I tried doing a little run through just now, and setting him on Warm/Sporty, but the chances didn't seem that great (though I was skipping through, and only got one new text saying something like "he said it in earnest" or something minor like that); I know he was studious my first (annoyed) round, but I think he might have been in the middle/"Mixed" personality wise, and he just felt really stubborn/whiny/annoyingly emo to me, a complete contrast to this new play through.
I've a feeling Cove is meant to be a bit Whimpy/Sensitive at his core, and they really play up the pubescent boy, which isn't much of a lie (have you seen teenage boys?! I know Netflix be playing, but they're all usual uncool bird chests, by rule of thumb); honestly, I'm waited on the tatted/ripped jeans Adult Cove more than anything
. However, praise aside, this isn't really the game for anyone that is at risk of saying "No Homo" after complimenting a same sex family member.
(I'm joking through this, though! So, no offense, even if you are an intolerant macho conservative, that's against Sad Bois and Hugging Sons, and gratiously uses the phrase "No Homo"!)
