I think it's reasonable to use a small DSL, I'm not so sure it's wise to build one considering you don't have much bandwidth. There are frameworks that exist that can do what you want.
For example, robot framework allows you to write your test in high level keywords. As a test engineer you can write these keywords in python, java, .net, or other languages (and there are pre-built libraries for all sorts of things like testing web apps with selenium, web services with REST or SOAP interface, desktop apps, etc). Your less technical coworkers can then assemble these keywords into tests.
This particular framework lets you write tests in a BDD style (Given/When/Then), a data driven style (tables of inputs and outputs), and a procedural style, which means you're not locked into one specific style for all of your tests. In my experience, different scenarios more naturally lend themselves to one style or another, so being able to be flexible gives you a lot of power to express yourself appropriately.
Robot framework tests are plain text and mostly read and write like plain english. The more effort you put into building a catalog of keywords, the more english-like it will be.
For example, here are what some test cases for a simple web app might look like:
*** Setup ***
Library PageObjectLibrary
Suite Setup
... Restart the server
... Open browser ${app_root}
Suite Teardown
... Close all browser windows
... Shut down the server
*** Test cases ***
Valid user can log in
[Setup] Go to the page LoginPage
Enter valid user credentials
Click the login button
Current page should be DashboardPage
Invalid user goes to the "invalid attempt" page
[Setup] Go to the page LoginPage
Enter invalid user credentials
Click the login button
Current page should be InvalidAttemptPage
Dashboard of new user contains no projects
[Setup] Log in to the application as a new user
Verify that the page contains a list of projects
Verify that the list of projects has 0 projects
There are other frameworks you can choose from that work in a similar fashion (fitnesse, cucumber, . The choice depends on type type of application your testing, and how technical your testers are.
Granted, with any framework you will need to devote time to learning the framework, organizing your tests and so on. In most cases, however, that time is much less than you would spend writing your own framework from scratch.