Trinity is one of the best frames but not widely played due to her DPS is only from her weapons. But she offers one the best survivability among other frames. All of her abilities are great and have a purpose to make you stronger. The mods I choose in this build is my opinion on how an allrounder trinity should look like. '
Duration: Duration is a special case for trinity as she can do great on either low or high duration due to her abilities. If she has a low duration, only one ability is being supported. That ability is an energy vampire, gain energy from the targeted enemy, and having low duration forces the ability to give 4 pulses of energy in a short time period. Overall, she gets instantaneous energy if the duration is low but it harms the performance of her other abilities. In some cases, players who play trinity can pull that stunt off and still have the same survivability.
Strength: Having a high amount of strength in this frame allows you to give a large amount of health and energy to your teammates while also giving them damage reduction. The energy from energy vampire; health and damage reduction from blessing; and health from the well of life scale with strength. The blessing can be easily maxed out with 100% health and shield restored with 75% damage reduction at the current ability strength. The energy per pulse from the energy vampire is 50 so a total of 200 energy from all 4 pulses. The well of life gives you 90% life steal to the target. The ability strength is necessary to make trinity a viable frame.
Arcane: there is no need to get arcane energize if you are running with a trinity as they already offer great energy back to other frames. Instead, you should look for arcanes that suit your weapons as she offers little to none DPS in her abilities. Using defensive arcanes is not ideal as you are not going to have a problem surviving at the current state of your build.
Adaptation: This mod is great for trinity especially if you are running guardian derision on the melee so you act like a tank for your teammates. The mod allows you to tank great if you are under heavy fire and using your abilities to increase survivability. This mod is very good but it is rare, in this case, if you don't have the mod you can switch it with health or armor mod.
Overall, Trinity is one of the best frames to tank while also proving support for the team. Her ability to give energy and health to teammates is unrivaled against other frames but the only con in her place as a support is the ability to cleanse proc off of allies like Oberon who is also a great support frame too. Other than that, she is the best frame for her roles.