For the most part, weapon usage alone should get you decently far (level 20?) but it will certainly come to a point in which you will want to be using your abilities often and in some cases, having buffs up 24/7 (frame dependant). Personally I don’t like ability spam, but some people/frames will practically kill everything with just abilities.
To increase the energy you have available to use abilities, keep your eyes open for these mods:
- Flow (extra max energy)
- streamline / fleeting expertise (extra energy efficiency, abilities cost less)
- Rage (damage to health gives energy, very useful on healthier frames)
(There are many more ways to get more ability casts available to you, but these are the easiest to get early on)
But again, it depends on the frame you are using. Some depend on their abilities to be successful and require truckloads of energy but destroy everything. Some don’t need to use their abilities much to be successful or their abilities cost very little. Two questions, which frame do you currently have, and which theme appeals more to you, a tank frame, support or damage frame?