My love for anime is dying, recommend me something to bring that spark back again

This is actually something that me myself is struggling through rn, in my case i try to watch and finish a show but never get around finishing it, rn as i'am watching Oreimo and tbh it's been real fun to watch. i've realized that i just want to consume light stuff enjoy watching them as per anything. For your case i would like to recommend two particulas anime them being

ODDTAXI
Durarara

i've fully completed oddtaxi and it's a gem and as per Durarara!! i've not fully completed it and consumed around half of s1. Both of these anime are really cool and you should give them a chance.

in my case rn iam only finding light anime enjoyable, thus watching Oreimo and tbh check those type of light anime too which kinda make you addicted but oh well try the two i've mentioned and i hope you get out of this burnout slop ur in rn. if anything doesn't work then taking a break from the medium is the best initiative

I would first give you the suggestion to clear up your watching list, either dropping/pausing shows you no longer have interest (atleast at this time). 60 is quite a bit to be watching. Maybe even just finishing ones youre close to being done with. Suggesting more shows for you to watch might not end up helping but ill suggest some anyway.

About a man deciding if its too late to achieve his dreams to go to space, and a brother who is very close to achieving that dream.
Space Brothers

These are on your planning list:
Maybe watching a long series (still short compared to others), will help your funk. Can't go wrong with Hunter x Hunter.
Hunter x Hunter 2011

Looks very simple at first but is able to set it self apart from other shonens.
Assassination Classroom

You asked for long series but im going to suggest these shorter ones anyway
Sonny Boy
PLUTO

One of the most fun animes out there + lovable characters, only one season but 0 bad episodes

Everyone that I recommended this to loves it, even if it doesnt end up as ur favorite, u wont regret watching~
Lycoris Recoil

based on what you wrote, maybe you should give existentialist literature a go.

Now for the anime recommendations, I do have to preface all of this with the fact that I'm not a huge enjoyer of anime. I have however loved some anime myself; most of them because they did for me what you described them doing for you. Apart from that, I have known many people that absolutely love anime and I have listened, maybe a bit too much, to their ramblings about the works that they love and why they do. Therefore I feel like my recommendations might work for you.

The classics:
MONSTER
A work that is supposed to make you think. I can't say much about the anime because I have not seen it myself but I have heard that it is a very good adaptation. If it is anything like the manga, it will really keep you on the edge of your seat until the very last second.

Ashita no Joe
You said you enjoyed Bakuman. While this isn't really all that similar, it is a work that laid some groundwork for more existentialist sports/achieving dreams/perseverance type of works. The manga is a timeless classic and I have heard that the anime holds up pretty good as well.

Maison Ikkoku
This is probably closest to your preferences, considering it is a prototype (and a masterpiece!) of romance (mostly aimed at males). It is, to me, highly interesting given the context of it's setting: young adults in the big city but tied down by socioeconomic status, societal expectations and the zeitgeist of the time period. Once again, the manga is absolute cinema, the adaptation well done, at least based on what I've heard about it.

Romance:
NHK ni Youkoso
It isn't reaaaaally about romance but there is romance. It's also the last anime that I will recommend to you which I haven't seen myself. It's the other side of the overachieving, reaching for the starts type of work, which Bakuman and Ashita no Joe capture. This one focuses on not achieving, not reaching and no stars.

Hachimitsu to Clover
I saw you enjoyed her other work and thought to myself, surely you must have enjoyed this one as well, alas I could not find it on your list and therefore this recommendation. I personally haven't seen either of them adapted (I swear this is really the last recommendation that I haven't seen myself) but both manga are in my favorites and I prefered this one quite a bit. To me it felt like it allowed a more intimate relationship with the characters and also depicted a world and time that intuitively connected with my own experiences. (You should also try Genshiken for a similar type of university setting) Last but not least, one of my ultimate absolute elitist anime friends kept pestering me about this work for years, if that doesn't say much, then I don't know what to tell you.

non-conventional works:
Ping Pong THE ANIMATION
An insanely well done adaptation with great source material. I didn't know that it would be possible to capture the artistic vision of the manga and yet here it is and it is breathtaking. The subtlty and symbolism of the story gets mirrored in the animation and allows for a fruitful engagement with its themes. It was a great experience for me to discuss this animation with likeminded people while it was airing and I hope that it can spark some insights for you as well.

Houseki no Kuni
I don't particularly enjoy anime but 3d anime is like a new layer of hell for me. This however felt good (even compared to the source material which is absolutely phenomenal). The sound design also carries a lot of its weight tbh. The only downside to this recommendation is that you will have to read the manga to find out the groundbreaking conclusions that this masterpiece reaches.

Haibane Renmei
Not sure that this even fits the category of non-conventional but it has an eerily calm atmosphere that really captures its audience (at least me). It's a mystery in just about every sense. Uncovering the mysteries however might also help you uncover some mystical moments within your own life. It is an experience worth having.

So Ra No Wo To
War. War never changes.

Special Award:
Kyou kara Ore wa
If you by any chance feel like watching a serious comedy about delinquents, give this a try. The manga changed me as a person and will forever be one of my most beloved favorites. I couldn't really fit it into a category but I think a special award for it is fair. The manga is better but the anime captures quite a bit of the feeling as well.

Honzuki no Gekokujou Shisho ni Naru Tame ni wa Shudan wo Erandeiraremasen
Shin Seiki Evangelion
Shoujo Shuumatsu Ryokou
Kino no Tabi the Beautiful World the Animated Series
Kamisama no Inai Nichiyoubi

a thing called fresh air and grass does the trick

on the pursuit of beliefs/knowledge:
Orb On the Movements of the Earth

on the joy of discovering a passion:
Backflip

i see you've watched this but it has 2 more seasons that you haven't watched i think:
To Your Eternity