A hydro-aero specialist is more of a nuker/supporter than a "battle-mage", since hydro-aero is strong in burst magic damage and crowd-control, plus healing.
I've never had a battle-mage kind of character, but that role usually means being good at magic and brawn in equal measure. So you probably want to get skills that boost armor, like Fortify and Armour of Frost, and a few other higher levels skills. In general any skill that helps the character sustain more damage in combat without needing a support to buff them.
As for (melee) weapons, you can either go for staves which do magical damage or normal weapons that do physical damage. Using physical weapons means you'd want to invest points in STR to make your physical attacks count. Using staves means you can skip STR and have more points to spend on INT, which boost both magic skills and basic attack damage. You can still be a "battle-mage", even when you do only magical damage. Keep in mind that you can use many Warfare skills with staves, but your damage would be magical, and since most Warfare skills incur physical penalties (like knockdown or crippled), you don't have a very strong synergy this way. But it does work; when an enemy has no armor left, anything goes.
So one idea for a battle-mage would be physical weapons, something like Warfare (65%) Geo (20%) Hydro (15%), STR or FIN (75%) INT (25%). The magic counterpart of this is the one in which you invest only in INT and the elemental schools, and use staves.
Or you can certainly do something like Warfare (50%) Pyro (50%), STR/FIN (60%) INT (20%) CON (20%), just to be flashy, if you already have a supporter/healer in the group.
Another option is to invest in Necromancy and go full physical damage. Necromancer + Warfare is a common idea, since Necromancer deals physical damage, which is boosted by Warfare. This is the typical life-stealing melee build. Depending on the weapon you're using you can invest in either STR or FIN, aside from INT. Although. this might not be your idea of a battle-mage, depending on whether you consider Necromancer traditional magic or not.
Last edited by Try2Handing; 03/03/19 09:00 PM.
