Dating site templates provided by ready-made dating software vendors are limited. They are also not very unique. That does not help you to deliver the right message to site visitors.
First impression is very important. Thats why many startups pay close attention to new design. You can do it on a budget:
Themeforest.net they have a lot of low-cost (10-20 USD) templates for various websites. The only flaw is that there are not many dating website templates in there.
Try 99designs.com its a community of designers who would be trying to make the best design for your website. Its a competition. You have more chances to make the design unique. The budget is also higher (about $300 USD).
Free design templates from your dating software vendor. Some have thousands (usually from previous integrations. Means not very unique), others a couple of niche templates (but they are specially developed for various software purpose).
But a lot of people still prefer to create their own design from scratch. Its a more expensive variant, but it offers you completely different experience. So why would they choose custom design at the end of the day?
The answer is simple its more flexible. If you have a vision of your dating web site and all you need is someone to put it into images, you are on the right track. A good designer can do miracles. With custom design you can edit elements, add more new items, and get exactly what you need at the end.
Its totally worth it only if you have a good designer. Otherwise you would probably get almost the same layouts and styles you could get ordering a ready-made dating website template. If thats your case, just order a template, take the source code and give it to a designer you have with your adjustment requests. Works very well and saves your time and money.
Its up to you to decide how to treat your dating website design. Some people just use default design of the dating software they have chosen, put their own logo and change a color scheme. And they succeed too. Sometimes startups with the best designs are never making it. Design without good marketing does nothing. So make sure you are ready to promote your website. When people come to check your dating website out, a great design will definitely help to retain them on a website.