Lambaowski,
The hardest part of this "job" is offering recommendations. Heck, I can't even predict what I might like, much less what will please someone else. For instance, my personal reaction to ECBlend RY4 is that it's a middle-of-the-pack Custom RY4, and yet I really like ECBlend Spicy RY4. Would you like it? I don't know. It's got a pretty obvious spicy kick.
Hangsen RY4 and Madvapes Mad 4 are both good choices. Hangsen is among the very best Chinese Classic RY4s ever made, in my opinion. That doesn't insure that you'd like it, but if you get some, at the very least you'll be able to say that you've vaped one of the Gold Standards of RY4s. Mad 4 isn't really an RY4 at all---it's a creamy caramel tobacco that leans just far enough into RY4 territory to be included on The Big RY4 List. That said, it's a pleasing vape.
A good thing about both those choices is that they're inexpensive. Obviously, Madvapes is cheap, but you can also pick up Hangsen RY4 for a song from Hong Kong vendors FastTech or VaporBreak. Among US vendors, CaterpillarVapes is a great source for Hangsen.
Another possibility (among so many) is Indigo Classic from IndigoVapor. Very nice. Also MrVape RY4. And we mustn't forget VaporTalk Dulcis and SmokelessImage Volt RY4. They've been in the Top Ten forever.
Finally, of course, at some point in your life, you should try one of the Janty RY4s, not necessarily today, but sometime.
Good luck and vape on!