Spell Combat is not modified by the Magus Card Caster archetype, but the archetype seems to be designed with a purely ranged focus. Spellstrike specifically says a ranged or touch spell can be delivered via a thrown weapon but without a modified Spell Combat ability, there is almost no difference between a Card Caster and a normal mage.
Is this in error?
And/Or is there any indication as to what the intention of the creators was when designing this archetype?
It was most likely an oversight on the part of the designers. James Jacobs has commented on this situation and mentioned that the problems stemming from the modified spell strike and spell combat ruins the existing synergy between the two abilities.
I wasn't directly involved in the Harrow Handbook or the card caster archetype, but it does feel like it ruins the synergy between the two for it. I suspect it wasn't the intention. --James Jacobs (Link)
From what I can see, the Card Caster could still use Spell Combat and Spellstrike with a one-handed or light throwing weapon that can also be used as a melee weapon, such as a hand axe or dagger. This is still quite different from any other spellcaster.
However, they cannot Spellstrike when using the weapon in melee, due to the modified version of Spellstrike. They also could not use Spell Combat with a deck, which seems to make the archetype of limited use.
