Ho-Oh Lugia Celebi ... Pichu (i don't feel very confident about it, without smash ultimate i'd say he's not there now, but since he is...)
i think suicune is damn close but not close enough (being competitive meta in gen 2/3 is good and being box legendary of crystal is significant too, but not as much as ho-oh and lugia's bigger box legendary statuses (and anime/movie roles) and celebi's movie boost (plus being equally competitive-relevant)), and esp/umb (obv reasons, being the most popular eeveelutions besides maybe sylveon or vaporeon, they even have strong presence in spinoffs) are in contention for sure too.
also raikou and entei are somewhere around top 10 at least (boosted by ova and movie relevance compared to sui) along with ttar (thanks to long standing competitive relevance and also presence in stuff like unite) and wobbuffet (90% thanks to the recognisability from the anime after all this time). marill and togepi might also be around there too but i def don't think they have enough factors to push them any higher than that really