It's controllable to a certain degree - it depends on the possible Enhancement Options and the Base Stats the piece of equipment currently has.
The first thing you want to look at is the Enhancement Options
This is the same for each equipment type, meaning for all Suits
, no matter what class, item rarity or level, the Enhancement Options are: Max HP / Max SP / DEF / VOID
This means that ONLY
these stats can be enhanced upon.
Now you have to look at the item's Base Stats
These are the stats you'll actually be enhancing. I have 3 of the ones from the Enhancement Options, so they will be enhanced upon as follows:
As you can see, there was no enhancement done to Max CP because it is not included in the Enhancement Options. You'll also notice there is no Max SP enhancement because I did not have Max SP as a Base Stat.
This is also why I only have 3 Enhanced Stats instead of 4.
is another example.
, the most ideal piece of equipment will have the 4 Base Stats that you want which are also included in the Enhancement Options such as this
I do not know all the possible Base Stat combinations but there are tons.