We work on marketing optimization a lot, particularly as it relates to lead generation systems.
Optimizing your marketing is a process that takes some level of research, some good ideas for what might work, and then a lot of experimentation to find out what really works and what doesn’t work. Then, turn off what doesn’t work and keep evolving and adding to what does work.
In my view, it is better to do this work internally than to use one of the lead generation services, as your knowledge of what works and what doesn’t work will build over time. A GREAT resource for finding some starting points is Marketing Experiments, which publishes a lot of great research and its newsletter is a must read for any marketer who is serious about optimizing their marketing activities and appreciates that it will take a lot of experiments! Use the ideas that apply to you as starting points for some of your marketing activities and make adjustments from there. You should get at least a 50% increase in your leads with no added expenses or you are not doing it right!