Which three characters should you start with if you're not great at action games and want to see the ending?
Does it matter who you pick in terms of story?
Yes, it matters who you pick in terms of story. There are three factions warring for control in the world and the faction associated with your main character (the first one you pick) ends up coming out on top and you fight their final bosses in their final dungeon. Charlotte's/Kevin's final boss is generally considered the easiest (though the penultimate boss of their route is a real doozy) especially if you make Charlotte follow the Light-Light route.
The game's not really action-based anyway. You move around, try to hit enemies with the tip of your weapon and try to avoid wading into enemy mobs during your cooldown animation and that's pretty much it. Almost all enemy skills that you need to actually worry about automatically hit, so there's not that much dodging involved either.
Anyway, there are lots of powerful teams, but if you're going with Charlotte in the Light - Light route, which gives her saber magic and Turn Undead eventually, you want some heavy hitters to balance her own lack of physical DPS. I'd suggest picking Riesz going the Light - Dark route (which gives her multi-target stat buffs, a full-screen level 2 tech and eventually a summon that mutes everything on-screen, making the issue of deadly counters irrelevant) and Hawkeye going the Dark - Dark route. (which gives him stat debuffs, a lethal full-screen level 3 tech, a single-target muting skill and a nasty Max HP debuff that shaves 20% of a boss' HP off right at the start of a battle) The combination of buffs, debuffs, sabres (including saint saber) and Heal Light will make certain your party will easily outlast later encounters.
Oh yeah.
It's mostly high level tech they counter actually.
If the screen is frozen by the skill used, the high level mob will counter with the strongest weapon in their arsenal.
if there are 4 foes, that means 4 screen clearing tech countering your characters.
You WILL end up dead regardless.
I'll let you imagine what happens when you try to combo 2 to 3 techs that way
I don't think there are actually ever 4 enemies on the screen at once anyway. ;) IIRC, the limit is set at 3. I could be wrong though. It's been a while since I played. It's also very rarely that you run into 3 enemies at once who have access to high-level techs. The whole "death counter" issue is mostly a final dungeon problem anyway since enemies with powerful counters don't appear THAT often during most of the game. And depending on the character, if you punched said enemies often enough to fill up your tech bar to the max, there's a very high chance that your level 3 tech blows them up before they can retaliate.