Okay, so from my early testing with the renown archetype, I have made some conclusions about some of the cards that people will be trying to play and some conclusions about the archetype as a whole.
The archetype is obviously pretty aggressive, curve is a big deal, most builds should be playing a few 1-drops and a few more 2-drops.
On that note, Anointer of Champions should probably see play. It's good for making combat with your renown creatures particularly difficult. It shouldn't necessarily be a full three-of, but some copies should almost always make the cut. I toyed with Elite Vanguard, but I don't really think it's good enough. It just gets outclassed far too easily. Kytheon is also obviously great, so that's something that you should always play. Finally, there's Sunblade Elf, which is just an excellent card, and might just be the best reason to be playing this archetype. The Elf should be a three-of in every list.
As for the 2-drops, Undercity Troll is awesome. Every version of this archetype should absolutely play all three. Same with Consul's Lieutenant. Depending on how aggressive you want to be, it can even be correct to play some number of Topan Freeblades, especially since 2-drop renown creatures are very good with Valeron Wardens.
As for some of the other creatures:
I tried Nissa, and I actually don't really think that she's good enough. She is a form of reach, but I find Rogue's Passage to do the job much better. Stalwart Aven is interesting, and I could definitely see playing a copy or two as a low opportunity cost evasive creature with good stats, but it's nothing exciting, and it's unlikely that four copies is the right number. Vryn Wingmare is another interesting choice. The deck is very creature-dense and making all of your opponent's removal less efficient is a great way to win games against more controlling decks, plus the body is a very decent way to put evasive pressure on your opponent. I find it likely that it is correct to play both copies. Valeron Wardens is quite good. When you play a large number of 2-drop renown creatures, it will cantrip fairly easily, and with combat tricks or even just against slower starts, it can renown itself and give you a big 3/5 as well as draw you a card. This is something I think should be played as a two or three-of in most of these decks. Citadel Castellan is just great, so three copies there. The deck is aggressive, so the top end should be sparse, but there are definitely some great options. Kytheon's Irregulars is amazing, so the two copies of that should go right in. Patron of the Valiant and Outland Colossus are massive finishers in this deck, and I think I could settle on playing two of each. The Patron's counter ability is extremely relevant in this deck and it's well-statted, and the Colossus is just a big deal. I've even been trying Juggernaut, as it's great with tricks and Rogue's Passage and just generally is a big threat.
As for everything else:
Wildsize is excellent in this deck. It's almost always a two for one, and it even gives trample so that your renown creatures still trigger. Definitely the combat trick of choice. I've tried a couple of removal spells in this deck. The one I settled on is Suppression Bonds, as it gets rid of a blocker no questions asked. I also tried Celestial Flare, but it was a little too hard to land reliably and just didn't pay off well. Wild Instincts does a similar job to Suppression Bonds, but just does it a little worse. There are even matchups where the Instincts would be better for its ability to add 2 damage to your subsequent attack, but I am certain that the Bonds is a better choice. Finally, Rogue's Passage has turned out to be great in this deck. It is a very easy way to get reach and can present a very quick, hard to interact with clock with any of the larger ground creatures in the deck. This is a clear three-of for me after playing with it a bit. I could also see Grasp of the Hieromancer being a beating in this deck, but I haven't tested it so I can't speak to it. I also tried Hixus, and I think that he's a trap card. When you just want to be attacking with everything every turn, he's little more than a 4/4 for 5, but I suspect that people will try to play him anyway because he is objectively powerful.
This is a classic creature beatdown deck, and I've been doing most of my grinding with it. It seems strong enough and surprisingly synergistic.
Mind posting your decklist?