Blood Bowl

Greetings.

I can't really answer all your questions because I own old Blood Bowl stuff and I don't know much about the new edition but I'm gonna share some ideas:

- Blood Bowl is one of the most awesome games ever made, especially since the 3rd edition. There's a living rulebook. I don't know what set of rules they use at present but I don't see why it should be bad since last time I checked.

- The least you need to play is a few teams, a board/pitch and special dice. I suppose the starting box comes with a pitch, the rules, the dice and 2 teams (apparently orcs and humans from what you say so it's cool). It's all you need to get started.
Afterwards you'll want to buy more teams, and you'll find tons of sites to get the teams you like, official or alternative. This is how I got my Slann team for instance. I'm considering buying next a Lizardmen team because they're a lot of fun to play and it's a team I need in my collection.

- About the teams I'd say most of them are balanced which is a real achievement in such an asymetrical game.
I mean, you can build the teams differently and the players will gain experience and evolve in various ways but still, the game will be pretty balanced.
The only trick is to learn how to play each team. Dwarfs don't pass the ball much and the elves shouldn't focus on bashing their opponent for instance.

- A fielded team needs 11 models and your roster can list 16 players if things haven't changed.
Unless you play a fragile team such as Goblins or Halflings you'll rarely hire more than 13-14 players at a time. But buying more models will give you flexibility to build your team when you "hire" the players. It's all a matter of taste. For instance I hardly ever start a Skaven team with a thrower. I rely on the gutter runners for ball handling. The throwers are hired later on in my Skaven teams and I use them as "linemen skilled with their hands". But I have friends who'll want throwers right off the bat when the team starts. As I said, a matter of taste.
GW boxes usually come with 11-12 players so you can play but you'll lack flexibility to build your teams. Other sites provide alternative teams and you can order 12-16 models depending on the options you wish. It's really cool to build a collection. This is how I got my Slann team including a Kroxigor.

- About the different pitches I suppose it's only a matter of design taste.

- Trolls, Ogres (and Kroxigors for instance) are "Big Guys" that can be hired by some teams. Ususally you can have only 1 Big Guy when available. Exceptions are the Flings who can hire 2 Treemen and the Gobbos who can have 2 Trolls. Again, I don't know the most recent rules and other teams may have the possibility to hire more than 1 Big Guy but the main idea is they're tough and usually add to the fun because there's uncertainty about the way they'll behave on the field.
Picture this: the Troll can throw a goblin (holding the ball or not) if he understands what you expect from him (he's got the "really stupid" trait) and decides not to try and eat him (he's also "always hungry").

Blood Bowl is amazing because there's a high level of strategy and a high level of fun in the same time.
Never hesitate to try crazy moves when you really need to score a touchdown or prevent your opponent from doing so. It may actually work and it'll be among the best gaming memories you'll ever have. I can promise that.

Here. I hope I've been helpful enough.

 

Khemri can field 4 big guys (Tomb Guardians). Of course their team wide Agility of 2 sucks!

 

Careful, very tough players such as mummies and tomb guardians aren't big guys per say. They don't have the "Loner" trait which is the usual "big guys" trait.
See https://fumbbl.com/help:LRB6KhemriSetUp

Fumbbl.com is a great site to play online and/or grab info btw
see a sum up of the teams here for instance:
https://fumbbl.com/help:LRB6RaceStrategy

 

I’d say that at some point GW will release the rulebook separately - I mean, they already have for Necromunda only recently. I’d say wait for a little while and see if they do release a separate one, and buy that along with the teams you want to play, some Blood Bowl dice and a pitch. Of course, if you or your mate wants to specifically play Orcs or Humans, then by all means get the boxed game!

I think Blood Bowl has special dice like the new Necromunda does. Luckily you can get separate packs of those coloured for specific teams, so you don’t need to buy the boxed game specifically for dice.

Team cards give the stats for your players as far as I can tell. All the teams that are released in plastic kits so far have cards I think, while other teams have a PDF that gives their rules (more on that below).

They are pre-prepared cards that represent the stats of infamous Blood Bowl players like Grombrindal and the Black Gobbo who can only be taken by specific teams but can really boost your team’s performance.

Players in specific teams are far stronger than others - for instance, Orc players are much better than Goblin players - but this is something you have to take for granted when you choose your team. If you want to play Goblins, for example, you have to take the fact that each player is much more likely to get horrifically mangled into account when devising your strategy - in other words, you have to fit your strategy around your team’s race, not the other way around as you would in 40K, Fantasy or AoS. This means that some teams are harder to play as, but that’s something you have to take into your stride if you want to play them. Each team has their own strengths and weaknesses - Dwarfs and Orcs are slow but tough as old boots, humans are jacks of all trades, Skaven and Elves are fast but squishy, e.t.c.

Pitches are largely customised for your team purely for aesthetic purposes, but some of them do have additional special rules you can put in to make your game more fun.

They are the ‘big guys’ for your team - several of these can be drafted in as additional muscle to help pulverise your opponent’s team and throw the ball further, which is especially useful if you play a squishier team like Skaven or Goblins.

Lately GW have released some of (in my opinion) the most boring teams the last few months, what with Chaos Chosen, Dark Elves, yet more Nurgle and most recently Vampire Counts-type undead, but I expect they’ll get round to Lizardmen eventually.

In terms of rules, there are rules for every team that doesn’t have new plastic models on a PDF on the Blood Bowl website called Teams of Legend to give everyone with older minis some rules until GW releases their race’s plastic kit (they did the same with Necromunda to tide players of all the gangs over), so there’s no need for you to use Lizardmen as Orcs until Lizardmen get their own team box. As for converting regular Skeletons that’s fine - as long as they represent Skeletons of some sort that’s OK, especially as you can choose to have 0 Zombies in your Undead team.

Here’s the PDF:
https://s19070.pcdn.co/wp-content/uploads/2017/01/BB-Teams-of-Legend-v4.pdf

I’ve never played Blood Bowl but I’d assume that the kits give you a playable team out of the box, like the Necromunda sets give you a playable gang out of the box.

I see that @tom1017 has already given you more details about the game itself but hope this helps in the meantime.