The Limited may be close, but it is not the same. There are many more standard features that you get on a Platinum over a Limited. On the Limited you would have to pay for those, and in the end, you will still have a Limited. My friend wanted to save money so he ordered an XLT with every optional upgrade, there is info online on how to order. He was still missing items like the upgraded sound system, enhanced leather steering wheel, LED lights, extra horsepower, suspension, enhanced interior and upgraded leather seating, etc. When he traded it in for a Platinum, he still had an XLT, and took a hit.
The extra horsepower and ccd has its benefits, especially with the tow package. The torque with extra hp and better gear ratio is scary fast, especially in sport mode. And the handling with ccd is smooth or tight when wanted. There really isn't an "all things equal". You will get close but not exact, as I tried.
When I went shopping, I started with an XLT with leather, because I had an Excursion XLT. My Excursion had a lot of addon features that I did over the years, like stereo system, 22" polished wheels with 285/45/22 Michelin Defender tires to name some. After extensive research, I came to realize that the Platinum came with all the features I wanted and then some, for very close to adding most of them on a lessor expensive model. And I would still have to modify certain items to achieve what comes standard with the Platinum.
Regarding the tow package, I have it, but it is hit and miss on stock inventory and an addon if ordered. I've never used it but like it for the extra cooling and gear.
I'm not downplaying any model Expedition, as they are all great vehicles. I'm just trying to answer the OP's question accurately. However, if you don't care about all those features, purchase a lessor expensive model and save money. I admit there are a lot of items I could do without, but I love and use them all, especially on trips.