A few points:
1. You really can't go wrong with any Sailor.
2. The large sized Realo was the launch prototype LE that was the size of the King of Pen. They made a few hundred and are unicorns. I've been trying to snag one for a decade, but no joy.
3. The Realo is really designed to be used posted. If it is too short uncapped, it is perfect posted (if you like regular sized pens). The main benefit is that the Realo tends to be a popular canvas for LEs in glorious technicolor with various embelishments. I'm rather obsessed with them (I have around twenty), and as we speak,
Bungubox alone has three rather fetching limited editions just launched. I'm lucky enough to own all three.
4. The Izumo is a lovely pen, but Platinum nibs tend to be a love-them-or-hate-them affair.
5. Conid was a passion project by the founder of Comex, a huge Belgian machining company. They paused production during Covid and have only recently restarted.
6.
Hakases are probably the pinnacle of Japanese penmaking. I have several, and if you can afford them, there is little anywhere like them.
7. Look at the
Namiki Urushi No. 20. It may be just what you're after. Urushi in either black or vermillion over a brass core. Oversized but not your usual black plastic pen.