The Sirens were aiming for a top four in their inaugural Superleague season.
But after placing sixth, Nelson wants to make improvements next term.
"We're delighted to go into season two with the same funders and investors, and when we look back at what we have achieved on and off the court, we had a phenomenal debut season," Nelson said.
"But in order to try to achieve more next season and to support our ambitions we want to secure more sponsors to join us on our journey."
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When asked whether funding had been secured for next year, Nelson - who is also Netball Scotland CEO - revealed: "Yes it has, but is it enough to do what we'd really like to do? Absolutely not.
"What we now want to do is look at how we can build on this year and bring more investment in to allow that continued growth and impact for the women and girls of Scotland."
More than 3,000 spectators came to the Sirens' opening game in February, the largest crowd in the Superleague so far this year.
"We came from a standing start with very little money and resources, but we managed to bring superstars in," added Nelson. "We have operated with integrity, passion and professionalism at every single step.
"We have set the standard around our operation, our volunteers are exemplary, our match-day delivery is exemplary, we put on incredible performances, we have challenged for that top-four position.
"We have no shortage of ideas, we know what we need to do and we know how we need to build on what we have done here.
"Is there more that can be done? Of course there is - and that's really exciting. For me it's about trying to grow our operation and deliver more significant impact off the court nationally."
Sirens chief operating officer Claire Nelson has ambitious plans for Scotland's first and only professional netball team.