There's also the
Predator Talons. Technically available at level 6 via the Ice Queen distress call. Personally, I wait until after Kara Quest 2 because you miss out on the (currently useless) Broken Psi-Amp otherwise.
I've never been able to beat Shizuya before level 9, but that may be the result of always being under-statted until after Zheng Shi. Maybe someone who actually spends their points would do better.
I think any 'build' is only going to be a very rough approximation limited to weapon type and general aesthetic. No Limit Break-like mechanic is the big thing, as that's the most important character differentiation in FF 7. Especially the original.
In comparison to the other party members, Tifa had very high Luck, highish Strength and Dexterity and low HP and Vitality. You might actually be looking at a Melee Smuggler, stat-wise. They can pick up Low Blow, after all. Alpha Strike combos well with Can Opener on a Melee Smuggler (Can Opener is Physique-based). Normally, I'd say Tifa doesn't strike me as wearing heavy Armor, but then, nobody in FF 7 does. Nanaki is effectively naked! The closest is Sephiroth's pauldrons.
Melee Smuggler also fits her role in the Remake. Low HP and Defense, high Single Target damage and the queen of Staggered Bonus Damage increases. Custom Shock Gear is probably the best weapon for this because Sneak Attack triggers off of Stun, meaning you don't need a setup round. The only really weird bit is Sneak Attack also scaling off Intelligence (Int/2), and Tifa's magic wasn't very good. Then again, FF 7 doesn't have do Intelligence = Magic like a lot of games, it just has Magic. Still, a good bit of damage is from Level.