Lvl 54 Crusader here! In my opinion go with STR INT build first or you can just follow the auto stats for holy cross build. The reason is if you go on full tank you will have a hard time grinding because your damage is way too low so its better to build a battle crusader (holy cross build) to progress faster. My Crusader can still tank even if I have this build so you dont have anything to worry about. Also if you are going for this build I suggest to craft the Lance weapon can be found in Morroc NPC or you can just buy it in the exchange if you have the money. I got mine at 300k+ zeny but I assure you it will be worth it!! Its the best crusader weapon accessible for now since it provides you atk 180 matk 180 and holy dmg +10% so it will complement your holy cross since it scales with atk and matk. My crusader now deals 5k on the first hit then 9k on the 2nd hit on holy cross.