Large company with existing traditional DB plan, so you have a current actuary and given your size, would assume it is a large consulting firm actuary and (hopefully) not a bundled insurance company arrangement. Your actuary should be willing and able to elaborate the pros and cons of converting to a cash balance arrangement, both in general and specific to your organization, as well as with respect to your employees - and for little or no fee. When you get into modeling potential conversion formulas and the impact on employee benefits, company funding cost and (often the most relevant issue) company financial statement (pension liability and expense), then the consulting fees can be substantial - as are the fees to actually implement the conversion. If your actuary is unwilling or unable to have a no cost general pros and cons conversation with on this then maybe it's time to find a new one.
If you are a public company and/or in the finance/banking industry, then I'm somewhat surprised you haven't already converted to cash balance or at least had specific material conversations about it. For a company/plan your size, the design discussion should be within the scope of your overall compensation and retirement benefits/total rewards objectives and include a comparative market survey, which kind of looks like what you're asking of this forum. Personally, I say consult with your actuary and possibly engage a total rewards consultant to determine what your company wants to provide, then drill down to your potential cash balance design on a top down approach rather than trying to go bottom up.
We've worked on many conversions over the years, large and small, various industries (banks, hospitals, retail, etc.) and public and private companies. The primary objectives vary, including simplify plan, lower employer cost, lower employer F/S expense, keep employees whole. If your actuary won't engage in a complimentary discussion with you, I have no doubt that one of the actuaries of our company would love to have a conversation with you (as probably others in this forum would as well). Maybe I've dug way too deep and you only want some basic cash balance plan design education and thought it's be easier to ask here rather than sift through volumes of Google search articles, but you will need a deeper dive at some point to determine feasibility for your company.