When creating your super character, there are many mental powers to choose from but the fields they fall within are limited. They are limited by what is usually referred to as the mind, body, soul divisions. For those who don't believe in souls but rather a form of mental spirituality then the use of power by the unconscious of the universal nature can take the soul's place. To keep this category understandable though, I've called it all spiritual powers. There is also another category whereby a character can enhance or gift a power to someone else while enhancing or detracting from their own. They can act like boosters or suppressors but as their power is considered more passive then the others characters with such powers often appear on the sidelines (unless physical contact is required for powers to be passed on).
When choosing mental powers it is quite feasible to assign a character strong powers in one or more abilities and weak in others. Sticking to sets of 2-3 powers maximum though, makes the character more understandable. This is particularly so if their weaknesses are easily discernible What makes a character sympathetic is a weakness or two that need overcoming and are hopefully being battled. This is why near invincible or invincible characters are interesting only for a short period of time. Attempts at sympathy and empathy wane after a while as characters prove impossible to connect with. No human is without weakness so an understandable super hero or villain must be too.
When choosing the powers to use you should also be aware that many powers already have aspects of two or more types of powers, eg, mental powers such as mediumship have a spiritual aspect and physical powers that are energy based can be considered as spiritual or mental manipulation of the body. This is especially the case for mental and spiritual powers as there is a constant argument over the mind/body split and whether there is a soul in society. The argument leads to an inability to accurately categorise a power unless personal opinion in included in the character and world construction. As this will happen anyway, I see little drawback in not being able to define powers more objectively.
Once you choose a power, disassemble it to understand just what your character will do with it, how they will use it and what the weaknesses inherent in the ability are. From there you are part way towards characterisation and plot development, particularly if you are set on playing on your character's weaknesses.
When thinking of mental powers most come up with telepathy and telekinesis straight away. They are the two main mental powers, after all, and effect someone else's mental state or physical state. Often enough, anyway. But there is little interaction between the mental and the spiritual with these two abilities.
Includes: psychic weapons, possession, mental projection, mediumship, omniscience, cross-dimensional awareness, psychometry, memory manipulation, mind control, precognition, empathy and many more abilities.
Powers of this nature draw on the unconscious mind, higher level thought, the emotions and the unknown spiritual elements of the world to be constructed. Once you open a character up to spiritual powers there needs to be a source or overarching world construction that allows for spiritual powers. This could mean gods or it could mean that all living beings, including the earth, has a spiritual side to their nature (like mana to magic systems). If these types of worlds are undesirable then having the powers be purely mental is the way to go. In doing so though, you will need to explain that there is no mind/body split, however you see fit. If the mind is the body then the need for a spirit is no longer there and the use of mental powers can be directly linked to any number of physical powers.
Includes: mediumship, possession, empathy, astral projection, omnipresence, summoning and more.
These powers can be unconsciously controlled by a character, can occur to their bodies without conscious control asserted, or have some elements of mental control but come more directly from the body or impact the body more than the mind. As there's often a mental aspect to physical powers these two categories are worth exploring together.
Includes: body part substitution, animal mimicry, healing, duplication (physical or temporal), bone manipulation, invisibility, superhuman longevity, fire breathing, poison generation, sonic scream, x-ray vision, heat vision, wall crawling, water breathing, shape shifting, elasticity and more.
Boosting or suppressing powers
Basically as above. Through touch or mental control a character can manipulate the powers of others and sometimes themselves by pairing or absorbing powers.
Includes: power augmentation, power bestowal, power mimicry or absorption, power negation, power sensing.
Technology and powers
Technology offers an obvious weakness when you consider the possibility of the technology breaking down but there remain the more basic weaknesses that come with being overly strong in one area at the cost of another. A suit will often inhibit movement while tech-enhanced light sensitivity would need to be shut off if a blast of extremely bright light came towards the character (and so on and so forth). Don't just stick to technology failing because if you consider the other weaknesses there to be drawn on you can also create possibilities for character and technological growth and development.
So when developing super powers for your character consider world construction, plot development, power pairing and weaknesses. Whether working from a weakness to world construction or plotting to characterisation, all these aspects of a story need to be considered carefully. Choose your super powers wisely.