In the past, I’ve used my own Compiled Domain Model module on projects. It generates wrapper classes based on your Sitecore templates (among other things). But recently, I’ve been working with Glass Mapper.
Glass Mapper doesn’t wrap Sitecore items, but rather maps Sitecore items to objects. The result is somewhat similar; you can work with strong-typed classes/interfaces and extend them if you want.
There are several ways you can configure Glass Mapper. One of the ways is by using attributes. The attributes map the classes/interfaces and their properties to Sitecore templates and fields. This works very well and is very flexible, but it can be a bit tedious to do manually.
But if you can’t use TDS (e.g. because of the costs), then here’s a good alternative. Kern Herskind Nightingale did something similar before. But my implementation supports: