Targeting only the first post in a topic

Is that possible? I want to style my thread template so that the first post in ever thread looks different, and I've been trying to figure out how but I just can't seem to work it out. Has anyone else cracked this one yet?

Variable for multi-mods

Generally speaking, I like to add the name of the forum a topic is being taken from to the beginning or end of the title of the thread I am archiving, when it comes to setting up multi-mods. Currently, I have to set up a separate multi-mod for every forum I want to archive threads from using multi-mods in this way. Would it be possible (I'm not sure if it's even technically possible) to have some sort of variable that can be added to the "Add to START of topic title?" or "Add to END of topic title?" (even just one of these would be helpful) fields for multi-mods? Or even some sort of setting I could turn on that would add this to a title when a thread is archived using multi-mods?

How to add friends / comments / posts to the profile

I was wondering, is it possible to add posts / friends / comments to the custom profile template? I read this in regard to adding comments but there is no information on how to add the link that actually allows members to add the comments being loaded, so I'm at a loss.

It could be my lack of JSON knowledge, but with a working template to start from I bet I could get something together.

<!-- |photo_url| --> variable for Post Rows

If possible, it would be super useful if the Post Rows have a variable like <!-- |photo_url| --> or <!-- |photo| --> (as in the main profile template, currently).

In RP forums that use fancy post templates, it's common to use one that includes an image of your character. Since a lot of the commonly used image hosts are experiencing issues, I think being able to use the personal photo in a post template would help (because you can upload your personal photo to the forum) and because it would make use of that image outside of it current exclusivity to the profile.

class / IDs on registration page

If possible, it would be awesome if there could be a class or ID added to the sections of the registration process that are custom fields that reflected which custom field they were. Similar to the way that the default profiles have something like "id="field_#"associated with them. Given that you can make it optional to fill out these fields, it would allow for some really interesting customization.

Not sure if it's possible (or probably, generally speaking) to implement, but thanks for reading and considering!