Hi. You should really put your chart up so that people can see the bigger picture around these aspects.
It is very interesting that all three of the outer planets are conjunct their lower octave planets in your chart. Any strong connection between any personal planet and any transpersonal planet suggests a conflict between acting purely as an individual, and acting as a mediator for collective energies. As with all conflicts, reconciliation is possible, but it requires conscious effort at keeping a balance.
Mercury, in and of itself, is trying to meet a very individual need by accumulating information and using it to create frameworks through which new experiences can be quickly understood and worked with. Uranus is trying to understand things in such a way that one can play a role in the evolution of the collective of which one is part. Mercury in Sagittarius seeks a shared vision under which people can unite with a sense of shared aspiration and optimism. So the sign placement of your Mercury Uranus conjunction may help you to integrate these functions.
Venus is the urge to be of value to the collective, but not to surrender the self to the collective. Neptune is prepared to sacrifice the self to the collective in order to escape the burden of individuality, and to redeem some collective wound. Here the conjunction is in Capricorn. In one sense, this adds to the conflict because Capricorn is an earth sign, and earthy consciousness values boundaries. But for Capricornian consciousness, the need for individual integrity is very much entwined with the sense of obligation to the collective. So again, there is something here that can work in your favour.
Mars conjunct Pluto in Scorpio suggests that your Mars, although in one of its traditional signs of rulership, will feel somewhat weighed down in one way or another. Of the conjunctions listed above, this is probably going to the be the one that will need the most careful handling. You may sometimes feel as though you must fight for your survival, and at other times that you must keep a lid on your assertiveness/aggression in case all hell breaks loose. Where Uranus is moved by ideas, and Neptune is moved by compassion, Pluto is moved by primal emotions. Society is less likely to thank us for our Plutonian contributions than it is for our Uranian and Neptunian offerings. Give yourself safety valves - perhaps in the form of physical exercise or some form of emotionally charged creativity. And if you get drawn into some 'war' against some evil in society, try to maintain a sense of objectivity along side that. If you get into power struggles, try to see beneath the crude surface appearance of the situation.
You could see these aspects as burdensome if you want to just live a complacent life and then die. But these aspects suggests that you don't want this, and that you will be happier if you take up the challenge to act as a mediator for change on a collective level in one way or another.