I'm a galka redmage at LVL 35. I find that i make an all around good player, able to cast magic with out the worry of dying due to hate build up. Also being a Galka i can hit really hard which makes me able to beat on the monster with a group can cast magic. If you going to go with a Galka redmage, i do suggest picking up the elder braces/boots. They helped me out alot. Also go with a Subjob that gives extra MP boost. So your stuck with black/white/summoner. I recomend doing black mage then you can warp around at RDM-34/BLM-17. Also hairpins are bad, best keeping good headgear on for protection. I havn't unlocked summoner yet, but that be the best if you just want to focus purely on highlevel redmage thats LVL 50 and beyond, such as haste. Like others say later in the game you cna pick up rings that convert HP to MP, but beware those cost alot. On odin server, Astal rings go for 140,000gils a piece!
One last thing. It's your character, your game don;t let other people tell you ooo that combination is bad. Well who cares you playing for fun. If it sucks and you enjoying your self then its a good combination!