Dikwena have already signed three forwards in Henrico Botes, Benson Shilongo and Thobani Kunene, as well as promoted eight juniors from the development ranks.
There has been speculation too that Stars may bring on yet another forward to compete with Ndumiso Mabena in the form of University of Pretoria striker Thabo Mnyamane.
But Johnson says he is still working on identifying areas where they might need to strengthen further.
“We are strong in a lot of areas, but we need to still identify those positions where we need to strengthen,” he told KickOff.com.
“There are a lot of very good free agents that are available right now, but for me it is about keeping my cards close to my chest to pick the right one.
“Because it is not just about what they on the pitch, but also do they have the right mentality for our squad and give us what we hope for off the pitch too.
“But we will see what is out there and whether it is right for us to being them in.”
With the side to compete in the 2017 African Confederation Cup after their third-place finish last season, Johnson may well need to bolster his squad as they compete on four fronts this season.