When nuclei contain Protons and Neutrons, EXCHANGE occurs. Protons become Neutrons, and Neutrons become Protons.
The "bag model" of Gluon-Quark containment agrees with observations better than the theory of "single elementary particle" Gluons. Gluon, as a cloud surrounding the nucleus, agrees with the observation that it requires more energy to move Quarks further apart.
With a single Gluon between Quarks, the force of attraction would diminish by square of the distance, which is not observed.
According to the bag model, Quarks in nuclei would be contained COLLECTIVELY by the surrounding Gluon cloud. Electrons, or negative Pions, could roam freely within this bag, forming Neutrons as they collide with Protons. This would explain the constant EXCHANGE of charges within nuclei, and the varying mass of Gluon, that we observe. No single particle in any of it's stable states has varying mass.
To remove a Proton from the nucleus, through the "bag" of Gluon, would require energy. This energy is currently defined as the "strong force". Removing Electrons, or negative Pions, would require less energy, once defined as the "weak force".
It has been established that the weak force is not fundamental, but merely a manifestation of electromagnetic forces [the surrounding Gluon bag]. The weak force is now called the "electro-weak force".
The theoretical fundamental strong and weak forces are not necessary by the bag model, leaving gravity and electromagnetism as the only necessary fundamental forces. Occam's razor should be applied in this instance.
It is logical that Gluon is a concentration of Dark Matter, available and present in all of space when particles are created by Pair Production. Higgs Boson are hard to create, are are not observed to occupy any area of space.