You are limiting yourself a lot by demanding a human inhabitable planet. Truely alien options would be habitable ice-shell icean worlds like Europa (it life truely originated in deep sea hydrothermal vents like the DNA if the last common universal ancestor suggests, Europa could be considered a prime example of the majority of habitable planets). I just metioned thus to show you that Earthlike might not be the standartmodel. Another somewhat earthlike but truly alien planet would be a liqid hydrocarbon world like Saturns moon Titan. Water takes the role of rock and ammonia-water mixtures the one of lava. There are some indicators that life in titans hydrocarbon lakes is not impossible .
A superhabitable planet is a concept proposed by astrophysicist Rene Heller that challenges the assumption that Earth has an optimal setup for life. On Earth the vast majority of the surface is desert, be that the deep ocean, icelands or actual deserts. The paper seeks to utilize a biocentic definition of habitability instead of the currently popular anthropocentic one. This results in these optimal conditions.
-Mass: approximately 2M⊕.
-Radius: to maintain a similar Earth density, its radius should be between 1.2 and 1.3R⊕.
-Oceans: percentage of surface area covered by oceans should be Earth-like but more distributed, without large continuous land masses. The oceans should be shallow; the light then will penetrate easier through the water and will reach the fauna and flora, stimulating an abundance of life down in the ocean.
-Distance: shorter distance from the center of the habitable zone of the system than Earth.
Temperature: average surface temperature of about 25 °C (77 °F).
-Star and age: belonging to an intermediate K-type star with an older age than the Sun (4.5 billion years) but younger than 7 billion years.
-Atmosphere: somewhat denser than Earth's and with a higher concentration of oxygen. That will make life larger and more abundant.
Change sky and plant color
On Earth we are used to a blue sky.
Well, sometimes at least. This video by worldbuilding youtuber Artifexian will give you a nice overview of the possibilities. Almost every skycolor and a number of very cool alien phenomena can be created by playing around with stellar spectral class, pressure and atmospheric composition.
His plant color section is a bit more questionable and looking up the absorbtion spectra of the plant based chlorophylls on Earth, a, b, c1, c2, c3, d and f in order to determine plant color might be more realistic. Note that chlorophyll f does not use visible light but infrared, making it very interesting for habitable worlds orbiting low mass flare stars. Imagine metallic blue plants which only use red and infrared light and attempt to reflect all other light in order to survive deadly flare events.
Total ocean planet with most seafloor in photic zone
For a detailed discussion of ocean planets watch this video by sience fiction and futurism youtuber Isaac Athur. Achepelago planets would probably be too earthlike and human inhabitability becomes very unlikely on ocean world with very deep oceans, because the lack of nutriants and minerals in the photic zone will make photosynthesis and thus oxygen production a unviable survival strategy. These world will be like Europa, only possessing a deep sea biosphere. As the oceans become deeper the planet will turn into a abyssopalagic one where water turns into an exotic ice at the seafloor. Not even a deepsea biosphere is likely to exist on such a world.
So a planet with little vulcanism and almost no tectonic activity is needed to make global oceans so shallow that seafloor within the photic zone becomes the dominant biome. Such a world would be a very alien water world and could be considered superhabitable. It would most likely be a superearth with more than 5 times the mass of earth so that it's profile remains flatt or a vulcanically dead world.
Sulfuric acid or supersaline oceans
This doesn't sound very cosy but would still be habitable for humans if done properly.
Sulfuric acid oceans can be expected on large Exo-Ios. Io is a Jovian moon which is very vulcanically active. Imagine a bigger version of such a vulcanic planet with oceans. The vulcanic activity would produce sulfur dioxide which would react into sufluric acid. All life in this world would be what we consider extermophiles.
Supersaline oceans could come be created by strong erosion which carries a lot of salt into the oceans. Think of a global dead sea. Lifeforms would be similar to our worlds halophiles.