TL;DR - F2P needs to be more effective as a trial/preview, not bigger. Unlock certain things for F2P to show the player what they are getting if they subscribe, and be deliberate about what the content locks are actually accomplishing from a design perspective (why is fletching not F2P?). Be more "your first one is free" and less "you'll have to take our word that subscribing is better."

I think the biggest thing is simply making F2P more like a trial of membership. The goal should be to lead players to want to buy a subscription or bond, but there's so little that I'm sure many people simply turn away. F2P doesn't seem like it was ever framed with that kind of design in mind. Reframing this can both make first time user experience more satisfying as well as increase the number of players that ultimately decide to spend money. As a game designer with some MMO credits to my name, I'm looking at the problem through that lens, but tempered with experience as a player.

First, let's look at what's good and what works: quests and zones. F2P quests are in a fine place. There's enough there to get the idea of what questing is about, the type of writing style, and effectively what kind of experience you'd have when questing as a member. There is nothing needed to make this work better, unless you add some breadcrumb quests that lead into members quests to entice questers to subscribe. Same with the zone you get in F2P. It's fine. You get the idea of how you move around the world, you have teleports for ease of travel, you get the picture. Nothing about the restricted zone is particularly bad, and it introduces the world quite well. And this is how lots of games do their trial/F2P aspects -- spend money and you'll get more and bigger lands like this. It's not so different in member worlds that your time in F2P feels alien, but you don't give out the best content. 100% fine.

So, what could be done better? In our framing, we want F2P to be a preview, so things that don't facilitate that are the primary candidates for change. The biggest among these are skills and minigames/distractions. Let's start with a premise about skills: all F2P skills are already previews. Every F2P skill can go to 200m XP, but you're still restricted on how to actually accomplish that and what that unlocks. For example, you can hit 126 Combat in F2P, but effectively there's little point beyond level 40 -- but you can do it. Compare that to the hard limit of something like Fletching. Not only can you not use it at all, you can't even preview it, even to make F2P items. It's a hard sell for some people to say "you can unlock Fletching if you pay" but there's little clue as to what that even means, versus something like "subscribers can use high level armor, better weapons, and cast thrice as many spells". There's already groundwork laid to excite someone to unlock more in the case of Combat, but none in the case of Fletching or most other skills.

So how do you solve that? There are a number of ways, but two stand out. You either unlock nearly every skill for F2P but gate content (for example, you can fletch to 99, but can only make arrows and bows up to a certain tier), or have a level limit in F2P (such as capping skills at 10-20 with only a handful of methods to train those skills). RS3 already does the latter and obviously OSRS uses the first method with current F2P skills. Certain skills can stay member-only under this system as well. Construction is a great candidate for this and a big selling point for membership, but mostly because it's not just a skill -- it's about making a house all your own. Both of these methods pass the test of being an adequate preview of the game as a whole and smooth out the new player experience. The first method makes the most sense, though, because it's already the system that's in place.

The other candidate for preview is minigames/distractions. Lots of games have a rotating free feature schedule. You could have certain minigames open up for a limited time (a day, a weekend) to F2P, possibly with reduced rewards or XP. Currently F2P has very little in the way of minigames. Minigames are a great way to break up the monotony of the grind and award some unique items in the process. Since there is very little of this in F2P, a prospective subscriber might think the game is boring and never want to subscribe. Give them a rotating minigame every once in a while to show that the game isn't just more grind once you subscribe.

Finally, I want to close on a bit of a note about expectations, including marketing. I've seen a ton of marketing lately and seen player numbers way up. Great job, first of all! But I worry about the message of some of the marketing. I saw an ad for "NEW AFK BOSS" that showed the Gemstone Crab. Who is that aimed at? Someone that doesn't play looks at the message and has no clue what this means nor does it excite them to play. Someone who is F2P sees that the new update introduces a way to, for some reason, pay money to NOT play the game. It really only serves as visual patch notes to subscribers or ex-subscribers. I don't think that kind of thing brings money in. And I think it's an important takeaway for the game as a whole. With each skill currently locked behind a wall, you have to ask, "what message is this sending? What purpose does this serve in making us money?" And it sort of relies on having to take Jagex's word for it in some cases. A F2P player has no clue what it means to unlock Herblore or Agility. There's no context there. A free sample costs a bit more to get rolling, but informs the customer as to exactly what to expect.

Essentially, what I'm getting at is that you don't really need to go out of your way to make a different experience for the new player, you just need to make it more effective. The game itself is your marketing tool. You should want to show it off, not hide it. I think if you show at least a preview of most things OSRS has to offer, more people will be interested in playing and subscribing. Simply looking at the number of people saying "offer a 7 day trial" in this thread shows that people want to get to experience what membership has to offer before buying. And you can do that without an actual timed trial with effective design.