Neat idea!

Are you asking for just self-recurring artifacts or artifact recursion in general because and are very good at the latter. For the former, your options are a little limited without . I'd look at artifacts with "unearth", or artifacts like Spine of Ish Sah, Scrap Trawler or Myr Retriever. If you want more general artifact recursion then I'd recommend Daretti, Scrap Savant, Goblin Engineer, Scrap Mastery, Trading Post, and Trash for Treasure. Most of these can be safely played at the precon power level. Some recursion effects that are on the stronger end are Goblin Welder, Portal to Phyrexia, Emry, Lurker of the Loch, and Academy Ruins. These are stronger in my opinion because of their efficiency, repeatability, and they possess fewer constraints.

As far as "how to build a precon level deck" goes, I wouldn't worry about purposely nerfing the deck per say, but maybe asking yourself "could a precon handle the synergies, resiliency, and value engines that my deck creates?". Ultimately though, I think the best advice I can give is to build the deck that you want to build, and that you think is precon level. Then play it against some precons. That will give you the best feel for where you deck is at and if you need to add or remove things.

Cool deck! Thalisse is a pretty fun commander. I am sorry to continue to beat a dead horse here, but I would also suggest the inclusion of Smothering Tithe. It's objectively one of the strongest cards in Thalisse (and most white decks to be honest). I see that you are worried about your opponents paying tax, but I want to re-frame it in this way: Smothering Tithe reads as "Either tax your opponents at least 2 mana or create at least 2 tokens on each of your opponent's turns". And that is just the baseline case. Any additional card draw continues to further tax your opponents mana base or advance your board state. The card is very, very strong.

Similarly, you might consider running Ophiomancer. You have enough sac outlets to reliably make tokens each turn.

I also found instant speed token creation to be very strong in my old Thalisse build. Cards like Grand Crescendo (doubles as board wipe protection), Inkshield (a fog that produces an instant army) and Secure the Wastes were pretty good.

One fun interaction that I used to run was Noosegraf Mob + Cathars' Crusade. It's a lot of mana initially, but it's such a dirty token engine.

Sorry for the double post, but I forgot to mention Earth Surge and Sylvan Advocate! These are no Craterhoof Behemoth but can make attacks with lands appealing if you can't find the big stompy lizard.

Profet93, Sandwurm Convergence doesn't make creature land tokens. They are just wurms, however, I can confirm that the anti-air clause is actually really strong. With that being said, since you are a lands deck PickleNutz, you could instead rely on cards like Constant Mists or Glacial Chasm to stay alive until you are ready to kill the table.

Have you seen any of the new cards from Brothers War? Awaken the Woods and Titania, Voice of Gaea  ^Meld + Argoth, Sanctum of Nature  ^Meld look like great fits for this deck.

Speaking of Titania, the O.G. Titania, Protector of Argoth and Zuran Orb combination works really will with Ashaya's "creatures are lands" clause.

The same can be said for Tireless Tracker and Scute Swarm

If you need another board wipe in mono-green, Ezuri's Predation is great.

Rude Awakening is a another Sylvan Awakening that lets you tap all your lands to cast all your spells while providing a way to untap them so you can still attack. Jolrael, Empress of Beasts is the O.G. of this effect. She is an interesting consideration since you can hold an opponent at ransom with her ability. I had an old commander deck built around her where I routinely thwarted board wipes by threatening to animate peoples lands in response.

You also have huge creatures so Rishkar's Expertise and Garruk's Uprising could bolster your card draw package.

Awesome deck! +1 from me