Q1: How's the gacha?
A: Gacha is split into several parts. Two are for mechs and the premium banner is where all your gacha suffering will go into. One is for regular pilot gifts. Last one that is separate from those three is the pilot gacha. It is not usually recommended to do the pilot gacha as you can get most if not all the pilots in the long run through the cafe system.
Q2: How's the difficulty scaling and how beginner friendly is the game?
A: Beginner friendly-wise, I'd say it's a bit challenging at first as you do not have a lot of S-ranked mechs to work with and the content ch. 10 and beyond will give you some trouble. It is recommended you start with a team full of maxed LB'ed A-ranked mechs as it is much cheaper to do so and you do not need dupes to upgrade A-ranked mechs and below. If you are upgrading your mechs, pilots and parts as you go further into the story, you'll have an easier time then. Events like the ICEY collab and the Halloween event also give you some good S-ranked welfare mechs.
Q3: Any romance system for the women (and men...)?
A: No marriage system here. There is an affinity system which is important in the cafe as the more drinks you buy for them, the more they like you and can be recruited to your pilot roster. Maxing their affinity through shoving gifts up in their faces will boost their stats. Story does have some romance going on like Slokai being ghey for Matilda (sorry IRUn) and a bunch of girls and women crushing/teasing on Bekas (your sort-of protagonist).
Q4: Am I doomed for being F2P and not getting all those top tier bling mechs?
A: Nope. Game is really generous if you play in the long run. Sure there are limited mechs that make your life easier but then there are regular S-SSS ranked mechs that are also good in non-PVP content. Furthermore, the game has these selector items that allow you to choose whichever pilots/mechs/parts/pets you want. The pilot selector item does cost real life currency tho. A lot of the top tier regular mechs can also be farmed in maps, though it takes a ton of patience and time to max LB them.
Q5: Are there collabs? When can I see Code Geass and Gundam making their way into this game!!!
A: Yes, there are collabs. So far, we have had ICEY, Armored Gull, Dangaioh and Zeorymer. We have an upcoming collab for Ultraman in December 2019. Future planned collabs are Gridman, Gurren Lagann, and Mazinger Z.
As for the second question, I will say no atm. Reason is Gameduchy's CEO and main dev isn't exactly on friendly terms with Bandai/Sunrise after they tried to buy his engine for their own Gundam games. So anything Bandai/Sunrise is out of the question unless some miracle happens in the future.
Q6: How haxx and cancerous is the PVP content?
A: When you see a full team of Nightmares, Asuras, Mephistos and Gawain GLs, then you know you're in for a bad time. Luckily, PVP isn't the core content of Iron Saga and there are many types of PVP that isn't as cancerous as the main PVP like limited arena where you build your teams in accordance to the weekly limitation rules set up for you or the random arena where you are given 3 random choices of pilots, mechs, parts, and pets and build a workable team around them. Limited and random arenas will be your main source of gacha currencies after you are finished with all the story content. Only problem is they are player level locked.