What payment gateways do you need that aren't currently included? Having all the same payment gateways doesn't mean much, if you don't actually need them. We are building more, and prioritizing by demand.
We do have plans to create new and unique order forms, ones that work well with a particular product like shared hosting, or virtual hosting, etc. One page AJAX forms, multi-step, and more. It's not as simple as making something work just like a particular hosting company when the order form needs to support a diverse range of products and services. We try to build things that are versatile, but we also see the need to build things that are targeted to a particular offer.
Aside from any tweaks to the existing order templates, our plans for more templates will follow a conversion of the client area to bootstrap. It will be significantly easier to create new and unique and awesome looking order forms once this has taken place. This will be after 3.1, which adds configurable options (among other things), which we see as a critical first step.