There Are Pandas, and Then There Are Pandas.
And this isn't either of them! The Pandas we're talking about here, are watches, not bears. And what got me thinking about them (again) was a link posted this morning by @cm.rook who pointed a few of us to the very attractive (and not terribly priced) Yema "Rallygraph" Panda which, in it's most traditional arrangement, looks like the one on the left, but can also be had in the version on the right: The model on the left is a true Panda, while the model on the right is called a reverse Panda. The reason for that distinction is clear--Panda bears, only come in the first arrangement. Now at this point, everyone should be thinking about the most well-know Panda, The Rolex Panda, which is actually a Daytona, and among Rolex Daytonas, the most famous of which is the Paul Newman Daytona, which was famous first, because it was Paul's, and second because it sold at auction for $17.8 million (US Dollars). The story of that auction is well-known so I'll only...
Nov 8, 2019
Pilot Vanishing Point: Way outside of your desired price range, but there's a reason I have 4 of them: it is a f**king awesome pen. No ifs, ands, or buts about it. If you can ever get one, DO IT. One of my 3 daily drivers. Get it in matte black for a very stealth look.
Lamy Studio: The 2nd of my daily drivers. Very smooth in medium. Excellent pen. My only gripe is that the grip feels too smooth some days. It is something others have commented on as well. The grip is perfectly smooth, untextured metal, so you may wish to try it before getting it.
TWSBI 580 Diamond: The final daily driver. As a piston filler, massive ink reservoir. I love this pen to bits. Should be right at or slight above your desired price point. May be considered a bit more showy than the Studio, with the clear body that shows off the ink and all. Be careful if you disassemble it, reassembly can be tricky, but there are videos on youtube to help with that.
Lamy CP-1: If fountain pens are too big for you, this is the pen to get. Roughly the same diameter as your average ballpoint, this pen blends right in. Lamy nib, which means it writes just as smooth as the Studio. I found mine in EF too dry for my taste, but that sound like it would be right for you.
Lamy 2000: Mostly for future reference here. I have a love / hate relationship with this pen. Very smooth nib, if you can keep it in the sweet spot. Keeping it in the sweet spot though, is like trying to balance a pen on the end of your finger. Not something easily done, and compared to the TWSBI 580 and the Studio or CP-1, not something I will spend the effort on, as nearly every other pen I have is far less finicky.
TWSBI Eco: Comparable to the Pilot Metropolitan with regard to price point, roughly 20$ or 30$. The least expensive piston filler I know of. Personally, I'd skip it and go straight for the 580, since the 580 feels far better in hand, but a decent pen still.
Inks: My daily drivers are used at work, which require waterproof inks, so Noodlers Bad Blue Heron in the Studio (nib creep is a thing, but the Studio is easy to clean) and Noodlers Liberty Elysium in the TWSBI. I have Pelikan Edelsten Topaz in the Pilot VP for everything else.
tl;dr: Get the TWSBI 580. Save money. Get the the Vanishing Point later.
I note that you wrote that you didn't like the triangular grip of the Lamy Safari / AL-Star. The VP has the nib at the top, near the clip, which means you will be holding at or on the clip, which makes the grip roughly triangular. It'll change a bit depending on how you hold the pen. If you've written with a VP before, and you're good with that grip and how the clip is, get the VP. Otherwise, get the TWSBI, which has a standard round grip.