Which swtor4credits weapon type would you rather use.
All information is gathered from,
Kotor being the game, that Old republic is based off and also made by the same company, so one could expect some (not all but at least some) of the same type of weapons to move over.

Disruptor Rifle

Damage: Physical
Range : 28 m

This disruptor was even more destructive than its pistol counterpart, and was outlawed on many worlds. Disruptors reduce solid matter to its constituent molecules. Painfully. Unlike typical blasters, disruptors ignore most types of personal energy shields.
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The Ion Rifle was the most basic upgrade of the Ion Blaster. It was a two-handed weapon designed primarily for destruction against droids, although it was capable of harming organic targets as well. The fact that it was an ion weapon allowed it to be extremely effective against all droids, from astromechs to assault droids.

The ion rifle was upgraded into a droid disruptor by both the Verpine and the Bothans

Damage: Ion
Range : 28m
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Sith Sniper

Damage: Energy
Range : 28 m

Despite its effectiveness, these modified blaster rifles were not often employed by the Sith. They preferred to engage their enemies up close and personal.
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Sonic Rifle

Damage: Sonic
Range: 28 m

More powerful than the pistol, the sonic rifle fires a blast of sound that causes a great deal of sensory overload in addition to damage, disorienting the victim.

I think certain abilities will utilise the different technology, but you're mainly going to be equipping Blaster-based weapons.

Of course, there is the possibility that components added to a weapon may add a particular type of damage, such as an Ion Chamber +5 Ion Damage (Droids and Tech Based targets).
TO
It seems there might also be a dagger and dart gun as weapons, which depending on your spec, will probably see a lot of use as well. It's been awhile since I have played KOTOR, I can't remember if there were any characters that used those types of weapons or if they were available at all.