Same as Marth with super long sword, you call it balanced?
Im saying its not balanced if you create an copy of a character version improved.
Take a gander at Roy's position on any Melee tier list. Range doesn't mean much when you're doin' less than half the knockback and damage of your clone counterpart.
Less knockback mean more combo so at the end egual of damage.
Roy also has lackluster hitstun, and recovers from moves' endlag slower than Marth. He struggles to combo off his moves even at point-blank. As a result, he can't combo off his ranged hits and combos worse than Marth from any range. That extra range of his is literally useless. Can't help his combos, doesn't give 'em KOs, and due to his unfavorable endlag it doesn't even help 'em space.
Furthermore, even if your (incorrect) logic was true, what happens after racking up damage? Roy has a single reliable KO move: F-smash. It's slow, won't KO unless it's sweetspotted at the blade's center, and leaves him wide open. Has the worst endlag of all his grounded moves IIRC. Meanwhile, Marth has a Meteor Smash with his D-air, can tipper ANY of his moves for high knockback, is quick and agile enough to perform gimps, can actually combo properly off his throws (even when a foe is at high percents) and has a KO move in his Up-B: unlike Roy. Even if Roy could rack up tons of damage (he can't lol), it's worthless since he struggles so much to land a KO on even a Jigglypuff at 150%.
Roy is an awful character, and is multiple tiers below Marth for many a reason. Range literally means nothin' if you can't capitalize on it, either for a combo or pressure. The best example of this is DK: he's got some of the horizontally largest moves in the game... and yet he's a god-awful character.