Ok so I was asked this and I really don't know the answers;
Is a Slayer//Investigator a good class to have for a skill monkey who can do some very nice stable damage without feeling useless like the Rogue sometimes [Personal view of the person who asked]
Is the Warpriest//Swashbuckler a goo combo. Does the scaling damage dice help out much or does most of the power just come from the spells?
I know that both of these combos grant full BAB and all good saves and a d10 for a HD.
Are these good combos to try out?
slayer/invest:absolutely its a wonderfully well rounded character who has very good stat synergy.
warpriest/swashbuckler: hmm i guess its workable but oracles and divine protection would shore up the swashbucklers real failing point, defenses.
I don't know about the first, but I'd advise against warpriest/swashbuckler: they are both heavily reliant in swift and immediate actions, and you would end up stepping on your own toes.
While I agree most Gestalt is to tag casting onto a martial to make the better Gish, I dont see that as always being the case. But the extracts help.
The Warpriest works well with the Swashbuckler if you are going Cayden Caylen because of his focus on Rapiers and so forth. Throwing 2d8 at 15-20/x3 +20 or +40 for a spent Panache point at level twenty is not Great but that is just the barest mix of the two classes, sure Cleric has spells to buff weapons.
9th level casting would be better, but I really have a hard time siding with Oracle as a combat class.
Daring Champion is a good trade off, but gets Precise Strike a level later, never gets Perfect Thrust and doesn't get Improved Critical as a free feat with EVERY light or one-handed piercing or slashing (via slashing grace) weapon in the game which to me is a rough trade off for better saves and adding another level to damage a few times per day at later levels.
But that is just my two cents
No idea, just seems like an odd choice for a class with so many healer and skill focused abilities and mysteries.