Quotei personally found in jot5, that the start is extremely hard, but if you endure the "many" game over at the start XD then you get very strong skills, and it's not that hard anymore, more like enjoyable.
IMO, it's kind of meant to serve as a slap to the face that breaks you of some bad habits in regular FFT where your actual Tactics involve recklessly zerg rushing your enemies with little regard for positioning or keeping near your support units, because only a very small percentage of battles actually feature enemies who bring something more threatening than autoattack to the table.
Specifically: Ramza starts out just as strong of a melee fighter as the rest, but he's also the only one who starts out with a support ability. After that, almost every ability he can learn is a support ability.
Link's in a similar situation. He's a bit more attack-oriented, but he still has ranged and support options that are worth cultivating. That's why he only has a single sword ability, but three ranged ones and three songs, as well as the option to switch his equipment on the fly. (In the rerelease, switching his weaponry won't even consume your turn.)
Dante, too, has some very good versatility with his weaponry. Unlike Link, he can't switch Styles in combat, but his base job can easily adapt to whatever battles you have coming your way.
- As a Swordmaster (his default), he's a strong DPS character. You can keep him there, but you don't have to, and I would strongly encourage you not to if you're looking to pick up more utility on your team.
- Using a dagger to switch him to the Trickster and picking up those abilities suddenly gives him a ton of utility. He's got two ranged attack skills, one self-Quick skill, and a Regen/Defending skill that not only makes him tanky as hell, but also replenishes his MP, allowing him more freedom to use special abilities. You don't have to switch him to a utility character, but the option is there.
- Using a crossbow to switch him to the Gunslinger makes him a strong DPS character, similar to the Swordmaster, but with the added benefit from attacking at range, which protects him from some harm.
- Using a hammer to switch him to a Royalguard turns him into a very tanky unit and adds the ability to buff the party.
Snake is designed completely around the idea of being a utility character. He's meant for surprise attacks, gambler strikes, chasing down and finishing off weakened targets, or simply distracting foes and being protected from the consequences of it thanks to his high Move, invisibility, and/or self-healing potential.
In fact, the only character designed to be a pure DPS character is Cloud. And considering the utility of Cross-Slash, even that's not 100% accurate.
The idea of backing away from pure zerg DPS is also why jobs like Knight and Ranger have major utility (Knight gaining heavy support, Ranger gaining heavy debuffing) while their equivalent Jobs didn't in FFT. It's why Wizard comes with the potential to inflict status on most of their spells.
It's also why the Chemist job suddenly becomes much more useful, instead of just having single-target heals and a billion different single-target cleanses. Sapling is powerful as hell, for example.
Basically, support and utility actually become important parts of FFT in Journey of the Five. The opening battles are hard because they're supposed to teach you early on to go get those types of abilities, instead of spending all your JP on pure DPS stuff. When you leave Lionel Castle thinking "aw man, that would have been so much easier if I'd had more MP," you put a higher priority on, say, Saria's Song or Encourage. (Fun fact: the three of the Five who use MP in their base jobs all have at least one way of restoring their own MP in said jobs.)