The most beneficial aspect of trine is that they are natural structures. You can benefit from them right away, no need to spend time and energy to build them. Just connect the plugs properly and they will take care of the rest. It's high return on small investment. They are the path of least resistance for any type of energy. They often lead to inner peace and balance. If you have a talent, trines will expand it without you asking. It comes easily and naturally, sometimes unconsciously. Trines are fantastic lubricants and catalyzers. People having many trines are often great listeners and soul healers. Their actions are so soft and sweet that you don't feel any hurt or need to resist. They can disentangle the most complex situations with infinite patience. They are not in a rush.
On the downside, trines don't create energy, but rather rely on existing ones. Think about multiplication versus addition. Zero times whatever equals zero. 0.5 times 0.5 is 0.25, but 0.5 plus 0.5 is 1. Multiplication does not always create a bigger result than the sum of the operands. Trines need a minimum threshold of energy in order to bring their best. If that threshold is not met, trines suggest a lack of motion and initiative. It's easy-peasy and sometimes right down lazy people. They don't need to make much effort and do face little confrontation. Therefore, they often don't build a carapace. Some can be totally incapable of maintaining a sustainable effort or to face strong and lasting adversity. They are much more comfortable and operational when life comes to them. They don't know how to "go and get it". They are terrible hunters.
Although trines have the best reputation amongst all aspects, they bear no boundaries or ends. You could end up being far too accepting or tolerant with unacceptable attitudes and beliefs, for far too long. If you don't have a strong ego to compensate, too many trines means a risk of dissolving into others, or into religion or spirituality, or anything that bears an infinite dimension. You could just lose and open up yourself too easily.
Relevant aspects: grand trines, sextiles and semi-sextiles
Other major aspects: conjunction, opposition, sextile, square and trine