I feel like there's a reason as to why Riven and Vayne broke besides direct or indirect buffs.

And this can also apply to champs like them that have semi-outdated kits. TL;DR: Runes Reforged left out crucial balance points that have affected certain champions to be what they are now.

There's been a large talk about Riven being very disgusting (which she is, despite being a "main only" champion), and Vayne being the god of all ADCs in the meta when they are no tanks. On paper that we only have the data for, they are very much in the red zone (but Riot has the absolute data, that agrees and disagrees with ours). But I could almost take it a step further and pinpoint why they and some other champs randomly have become strong, with or without being touched: Champion strengths and weaknesses haven't been adjusted around game length ever since Runes Reforged. We got some stat increases and decreases, but for the most part ratios, game time/build cost weaknesses, and cooldowns were left alone, which is the issue. I will speak on this later.

Don't believe me? Since runes reforged, what is the one stat that has appeared in abundance compared to previous seasons? CDR. Who's kit benefits strongly from cdr? Riven. What are the two things that haven't been adjusted for her since runes reforged (9.4 was only VFX for her)? Spell cooldowns and ratios.

Here's another one but a different reason. Since runes reforged, what has decreased compared to previous seasons? Average Game Length. What has risen to the highest its ever been in previous seasons? Gold Generation. What was Vayne's primary weakness? Being weak early. Has that changed? Yes. At roughly what time and how many items does Vayne hit her strong power spike in previous seasons? Roughly 40 minutes full build. What is it now? 24-26 minutes 3 items (BotRK, Rageblade, Zeal item). Yes, rageblade is a strong reason as to why she's strong (it removes a aspect of skill that crucially determined how good a Vayne was), but these other things helped attribute alongside her buffs to put her where she's at. With higher gold generation, power spikes come sooner than they have in previous seasons.

I know i'll will get people that will say, "But for X, that isn't true." and they would be correct, but in other situations it could be wrong. Since runes mainly give you boosts, that also means they don't create massive weaknesses, leaving that aspect left out. That means that lane pools and items are the only things dictating a champ from being strong or being weak (besides a very decent lack of certain types of runes). Here's my analysis on what I call the Triangle of Champion Core. The triangle consists of Ratios, Game time/Build Costs, and Cooldowns.

All 3 of these imo originally dictated how strong a champion was regardless of items or runes. Now what changed about this that honestly has removed that? Well, first off, CDR is in huge abundance regardless of AD or AP, shorting up any weakness for champions in that regard. Second, Game times have gone down and costs have been "lowered" due to the massive gold generation. Lastly, Runes Reforged never adjusted the ratios of spells for certain champions, allowing them to gain more offensive power than before even if bases got touched. That leaves the triangle obsolete in most situations and only for champions who haven't been adjusted to the new rune system.