consider: dreamwidth

pros:

• remember livejournal? it's like that, but not owned by the russian government. if you liked cohost because it reminded you of the old web then this may be exactly your jam! it's a fork of livejournal's code operated by people that used to work on lj before the new ownership.
• since dreamwidth was originally created by and for horny fandom people as a refuge from livejournal's censorship bullshit, there's no corporate garbage and no advertising. you can post unhinged shit to your grubby lil heart's content knowing you're safe from getting purged to please The Advertisers, which means...
• 🚨 ADULT CONTENT IS ALLOWED! 🚨 and you can add content warnings to it! don't wanna see horny stuff? you can hide it entirely too! source
• no algorithm. your feed is 100% accounts and communities you follow and that's it
• multiple pfps (15 for free accounts, 150 for paid accounts!) so your posts can have a particular icon to match the mood of your post or comment!
• privacy control for each individual post! you can control access to your posts to a very high level, so for example if you had a friend group that wants to see your oviposition content and a group that wants to see your spicy meat pics you can make a special little group that only they can see. you can even make a post that's locked just to your little ol' self if you want to.
• communities! same as they were on livejournal. you can create and join communities around interests, roleplay, whatever. your personal account can just be a regular ol' journal for you and your friends and stuff you want to be seen by more people can be posted to a relevant community!
• if you like long form text blogging this is not a bad platform to do it on. it's got longevity and has been around since 2008
• it has a DM system
• notification control (you can mute certain notifications if you don't want to see them)
• it's still being actively maintained! the most recent staff post as of this writing was on september 4th. (thank you @contextual for pointing this out!)
• paid accounts are reasonably priced ($35-50 for a year) and have nice benefits, such as more pfp slots, customizable journal layouts, and more image hosting space! if you end up liking the platform and using it a lot, it's a pretty sweet deal!
• supports RSS! both by each blog having its own feed, and being able to add RSS feeds to your own reading page. how to create or subscribe to an RSS feed, RSS feeds for all accounts (thank you @ur-gothmom !)

cons:

• no direct image hosting. you can embed images in your posts but they have to be hosted offsite EDIT: you CAN do image hosting (up to 500mb for free accounts), with paid accounts getting more upload space! see more information about image hosting here (thank you @contextual again!)
• no app, due to being web 1.0 social media. but like cohost you can access it in your phone browser. i don't know how the mobile layout is or if it has one. there are site skins that are mobile friendly, such as "gradation horizontal" and "lynx" and journal layout "starflower" (thank you @neckspike for mentioning this!)
• there's no 2fa. for some folks this is a dealbreaker and i can understand why. however since nobody has heard of this site beyond livejournal oldheads it's not exactly a high priority for hackers, but maybe don't use it as a repository for your social security number and passwords EDIT: 2fa is available as a toggleable beta feature and has been available since 2020, per @here-and-anon - there's a post about it here
• there's no native feature for account swapping and you have to use a browser addon called LJ juggler to switch between different accounts easily if you don't want to log out and back in every time.
• it's an old site, so i'm unsure how active the existing userbase is. you probably won't get much out of it if you strike out by yourself. there is an active userbase in fandom/fanfic circles, so if you like fandom stuff, it's a good place to go if tumblr isn't your thing! (thank you @xyzzy!) however, even if you are not into fandoms it's easy to make something of it by populating communities with likeminded friends!

neutrals:

• the web 1.0 interface will take some getting used to if you've never experienced livejournal. even if you've used lj in the past, chances are it's been a minute since you've been on there and will have to adjust.
• no "likes." you either interact with a post by commenting on it, or you don't. this might be a good place to relearn how to comment on things, as the only numbers are the number of comments a post gets. this might be a positive for some and a negative for others, so i'm sticking it as a neutral quality of the site.
• HOWEVER, if you want to save posts you like similar to a likes page, you can add them to a private "memorable entries" list that can be organized as you please (@here-and-anon thank you!)
• no reblogging/sharing system. your "posting things to be seen and interacted with by other people" platform will be in communities, it's otherwise more like an interactive journaling site. you post a journal entry, your friends can read and comment on it.
• communities basically function similarly to subreddits and identical to how they functioned on livejournal, they're a centralized hub for posts centered around a specific topic or interest. so for example if you wanna post about blorbo's adventure, you can search the blorbo's adventure tag to see if there's any communities dedicated to blorbo's adventure (and if there are none, you can create one!), join that community, and make a post to it and all the users subscribed to that community will be able to see and interact with it!
• there is a cap on blogs you can subscribe to and grant access to (1000 for free accounts, 1500-2000 for paid accounts). personally i think this is a positive feature because i cannot fathom being followed by that many people (or following that many people myself) as that would just give me anxiety lol, but you may feel differently. either way there's no "going viral" on dreamwidth. this is not a website you come to with the goal of going viral.
• because there's no algorithm, there's no discoverability. everything is in tags and communities. search tags, find profiles and communities that have those tags listed in their profiles, check 'em out!

tl;dr

i think dreamwidth is a worthwhile contender if you want a cozy-feeling space online that's just you and your friends on the old web and you're apprehensive about going back to the rat race of modern microblogging sites. however, it is dependent on people being there to make it work best for you. thus, dreamwidth is best enjoyed with friends!