Warning: non-sexy answer ahead.
It is gonna come down to the hustle and charm of the person running the nonprofit. All the great sites and tools that have come online in the last number of years to help nonprofits is great. You could spend a month just filling out profiles and putting together videos to get listed on all them. It wouldn’t have much of an impact on your donor base. The reason is that people are backing your nonprofit just as much as they are backing you.
When someone donates it means they believe that you can do something about the problem your nonprofit is addressing. As your nonprofit grows it gains history and stories you can point to those as proof to the work your are all doing.
And those profiles you setup online? The people going to them are mainly sent there by you. Some sites will present or display your stories better than others. At the end of the day the majority of traffic will find it because you sent it there.
Very few people click around the Internet waiting to give away their money to some nonprofit they’ve never heard of before.
My suggestion would be to invest in good membership software. Use it to track your donors and to capture contact info for people you meet. Be aware of who is interesting in your nonprofit and ask for their emails. That list you build, and the emails you send them will prove way more valuable 99% of the time in helping grow a nonprofit to sustainability.