I believe the rumors are true and Samsung is going to create another line of smartphones using premium materials called the Galaxy F. While I do think metal feels premium, I do think it can be overrated. It dents, scrapes with a different color underneath, high SAR, adds weight, and signal can't always come through. I have seen some dinged up HTC One's that don't look so great with dents you can't just rectify so quickly like with plastic/removable back covers from Samsung. If the Galaxy F is really F for false rumors or just another S4 in a nicer casing, then I believe Samsung will put all their eggs in one basket with the Galaxy Note 4.
In fairness, the S5 doesn't look so bad after watching the Android Authority, The Verge, and Samsung Mobile first-look videos. The black version looks pretty decent but still not on par with the likes of Apple, Sony, and HTC. Samsung didn't use glossy plastic material that attracts fingerprints and would feel slimey after extended use. And while it is water/dust resistant like the Xperia Z series and has a fingerprint scanner like the iPhone 5s, the most interesting feature is actually that heart sensor. The Xperia Z2 might look better but generally more of the same spec bump and a much better screen while the Galaxy S5 seems to have more interesting features and FORESIGHT like a heart monitor, WiFi ac MiMo, and still providing a memory expansion slot up to 128 GB and a removable battery
Some people are forgetting Samsung has already made their way into the medical field with many of the medical equipment manufactured by them. No different than LG getting into the appliance business. My portable air conditioner is made by LG and my washing machine is made by Samsung. They don't just make solely portable electronics or TV's. I guess Samsung is now targetting more health conscious people and the much older crowd.
I expect the Galaxy Note 4 to have ALL those features that the S5 has and then some! And the best designed and interesting gadget by Samsung that was announced in MWC was NOT the Galaxy S5. It was the Gear Fit. I would rather get a Gear Fit than a Galaxy Gear 2 even though the latter looks pretty decent and taking photos is more obscure than Google Glass. Galaxy S5 with a revamped S-Health, heart sensor, and Gear Fit makes a very interesting health conscious combination.
I wouldn't say that the Z2 has a much better screen. They have the same resolution and the difference in ppi is negligible when it gets that high. It just comes down to wether you prefer Amoled or LCD displays.