Sub classing sounds scary at first, but people over complicate it and try and min max..I love the game, but I never ran into anything that I had to min max for. Play what ya like and I am sure it will work out!
It's not just the min maxing, enemies get huge buffs on HP and aggressiveness later on in the game, and class/subclass combos that don't mix well together may end up having trouble more easily with the later content than the class combos that do mix well together. ^^;
But, well, that's for much later in the game, it's unknown when such content will start being released anyway (content with enemies at lvl 75 or above). Until then any class combo works, and if it works like the JP version, there's even small stat bonuses that affect the whole account from getting each of the 9 classes to lvl 75, so it's not a bad idea to experiment with different class combos during the easy part of the game.
Yeah I've never been a min/maxer but I've always loved range is PSO hence my main choice but it would be nice to be able to throw out some heals too
It may be worth keeping an eye on Phantom, unknown when it'll be released in the NA version, but if it works out like the JP version when it does get released, it will need 2 of any of the current classes at lvl 75 to be able to unlock it.
Phantom is a class that uses Katana, Rifle and Rod in different ways than the current classes, and it can use technics with any of the weapons (though when using katana and rifle, it's recommended to use only support techs).
I tried searching for a video that shows off Phantom's rifle, I was able to find a video that only shows off the rifle's actions, though note that it includes footage from an area that wasn't in the closed beta (no enemies or bosses are shown in the video though): https://www.youtube.com/watch?v=8yxpLAqmjso