Any of those can work. There's also an Iroran paladin, a skinshaper druid, maybe a medium of the master (psychic magic rather than divine but it should look similar), and you can probably do something with a cleric.
Anything more specific you're looking for?
Paladin + antipaladin is asking for trouble yes, and a paladin would be a mistake in Skull & Shackles anyway. There's plenty of other options.
Depending on the rest of the party, there might be a particular need for a character who can do very well at profession (sailor) - it's mentioned in the player's guide, this shouldn't be a spoiler. A cleric or warpriest can be that but have a possible skill point problem; the skinshaper druid might be the best choice if there isn't another expert sailor in the party. If there is then I've got no advice, oracles, warpriests, druids, mediums and clerics can probably all fit your criteria as specified.
What works for you depends on the ratio of martial prowess to casting you want. An Ascetic Oracle for instance is light on the martial side but a powerful caster (at higher levels it turns into somewhat of a Magus), whereas a Paladin of Warpriest would lean more towards the former.
How well any given build would hold up in combat depends on the optimization level of the group. What you have to realize is that mechanically, unarmed is usually a poor choice, but there're three ways to compensate for that: Handwraps offer TWF with the enchantment cost of a single weapon, a bunch of feats are unarmed specific (especially the ones like Domain Strike, style feat chains alone aren't usually worth it), and obviously there're class options that support the playstyle.
Not wearing heavier armor is actually not that easy to make work - you need either to go dex based, take an archetype that grants stat-to-AC, or dip into Monk for that. I hopy the Wizard-y guy has Mage Armor.
For healing spells, you don't necessarily have to bo a divine caster - most of the spells are on the alchemist list, so n Alchemist or Investigator with the infusion discovery can do the job very well (better than an Oracle or Druid, actually), and would help on the skill front (especially Investigator). For divine casters, Cleric followed by Shaman are easily the best at removing nasty effects, and while neither have any special unarmed options, they'd work well with a dip into unMonk. Nature Fang Druid, too. If you want something charisma based, Elder Mythos Cultist Cleric with a dip into Scaled Fist unMonk is a possibility.
A dex-based Investigator, Warpriest (w/o Sacred Fist), or Inquisitor (possibly Sworn of the Eldest for extra faceyness) can work well with TWF, since presumably you'll start at a level where an Agile AoMF is affordable. Dipping a 6/9 caster into Monk weakens the castign stuff, obviously, but is still doable (Jinyiwei makes Investigator wisdom based).
Pei Zin Practitioner Ascetic Oracle that looks like one of the pirates from the 3rd pirates of the Carribbean movie?
Nice amount of healing from that archetype. Big swift action heals on yourself means you need not worry too much about being hit. You can just laugh at them in a mocking piratey way as their attacks are undone before their eyes.
If you can grab the fey foundling feat the heals get even bigger.
Maybe your herbalist style lay on hands can be done by chewing the herbs up like chewing tobacco, giving your teeth a blackened piratey look and allowing you to spit on your friends to heal them, like the deplorable pirate you are.
Yes an ascetic oracle can do ok in melee due to a combination of their monk damage and spellstrike. That and the crazy good self healing.
At low levels warpriest self buffing is very nice to have, but higher casting is nice to have too, especially so you get quicker access to restoration and heal.
Sacred Fist holds up pretty well. Self-buffing as a swift action is rather nice; divine favor, divine power, prot vs. whatever, shield of faith, cure spells and other condition removal, invisibility purge, etc...
Need just as good stats as the Monk, but they play double duty (at least Wisdom, granting AC bonuses and all that), and you have some bonus feats so you can get Guided Hand if you want to cut Strength out of the mix.
Might be able to convince your GM to let you mix some of the Unchained Monk stuff in and that will really up your effectiveness, but the standard bag of ki tricks are pretty nice.