Go for 27 str/40 dex build. 40 dex is the sweet spot because anything beyond 40 the damage difference very minor although 45 dex allows faster casting. Same goes for 27 str, anything beyond 27 is minor when you 2 hand it. Then pump in the rest of your points to Vit and End, resistance is a useless stat. Weapons that take advantage of dex would be Uchigatanas,Iaito,balder side sword,great scythe,pike,gold tracer.etc because these weapons have a A/S scale in dex when upgraded. For str woudld be Man serpent greatsword,demon machete,Zweihander,large clubs.etc
Weapons like claymore takes advantage in both str and dex because they have a C scale in both.
As for pyro,it doesn't scale on any stats but scale on the equipment upgrade so it goes with any build. If you want you can also pump 5 more points to int so you can use great magic weapon spell for extra damage.
Would you recommend the same for a warrior? If anything I just want to be able to cast basic healing and fire spells.
Also what weapon should I try upgrading after the drake sword? I have a gargoyle great axe.