Game mode question from a new player

Hey,

Just started up the game this week and am enjoying it.

After playing about 30 games and starting to pick up some skill at the game, I was wondering about the different game modes and my personal experience with Apex.

I didn't really use the game interface (store, legends, game modes) for the first dozen games. I just played the game. It wasn't until I came to this subreddit and people were discussing SBMM and "ranked" that I found the training, ranked, etc.

Obviously I'm Bronze as I'm starting out.

My question isn't what SBMM is, or the pros or cons, I'm just looking for some feedback on my experience.

I'm around 30 matches played overall. 1 win, although my teammates did all the work, I just survived to the end. I'm still learning but have been able to get kills on both unranked and the start of Bronze. Nothing crazy, 1 or 2 kills, but the last day or so I've felt comfortable enough to be calm in both ranked and unranked when I encounter an enemy.

I'm wondering about player banners. If I play unranked I get teammates with hundreds of thousands of damage for example. Along with different players who have a banner with 8 kills. It seems like a purer BR experience in theory. Is this true?

If unranked is a bunch of people dropped in the game and the best players winning, isn't unranked technically going to be the more difficult mode in terms of getting a win? I've read that people are playing more casual on unranked, but wouldn't the randomness of players, as opposed to tiered play, throw a wrench in casual play?

I know the SBMM algorithms are used on some level on unranked, but wouldn't more random players with a higher skillset slip through?

I'm also wondering what the max cap of players is per game and why the game has had me in squads of 3, 2 and by myself? Is this common?
I've been the last/partial squad in other games, but this game has fired up without a full squad fairly often.

At my level of the game, just starting out, Bronze, does squad balance even matter? I'm thinking any 3 characters work?
At the higher skill level I completely see the need for balance, synergy.

My last question is player etiquette.
On the dropship landing I've got teammates grabbing supplies from supply pods I just opened. They'll open one, loot, and run over to mine taking a secondary weapon, when I'm trying to equip it as a first weapon.
Also have teammates looting every kill box.
If I can, I always wait until the person who got the kill loots the box.

Just wondering if this is a common experience, outside of playing with friends?

Thanks again for any feedback.