The Canon is a business class projector and should be a significantly brighter model than the Panasonic.

I have used the Panasonic several times in home theater installations. It's rock solid in that regard, but it is not a business class projector.

The things you want:
3-panel design. So, you are good choosing a 3-LCD (Epson, Panasonic, etc.) or LCoS (Canon).

BRIGHT! That's mostly what business class presentation comes down to. The brighter the projector, the better it will look.

Be aware, that if your Dell projector has a LOT of hours on it, then it may just be asking for a new lamp. When a projector's lamp nears end of life, it can be less than 50% as bright as when it was new. This is important because contrast and colors will severely degrade.

I'm not sure what your budget is, but Epson's refurb website is a great place to look as well.
https://epson.com/Clearance-Center/Projectors-for-Work/c/cc302

You are at about 400 bucks for a 3500 lumen model. But, it comes with a warranty, proper HDMI connectivity, wide aspect ratio, and a new lamp. All of which will make it a pretty solid way to go.

I still often recommend that course to get more bang for the buck down the line.

Depending on screen size, you can get something like this for under two grand...
https://epson.com/Clearance-Center/Projectors-for-Work/PowerLite-5535U-WUXGA-3LCD-Projector---Refurbished/p/V11H824120-N

Please feel free to call me if you want to talk about things a bit or keep asking questions if you want some details. If you provide a budget you are aiming for, I may have some time to offer up a few ideas that may work well.

It can be frustrating when the budget is low and you are kind of stabbing around in the dark for a solution.

But, sticking with 3-LCD/LCoS and then going BRIGHT is the way to do it.

Be aware that the current recommended standard for business use is 1920x1080 or 1920x1200 resolution on the projector. That matches up with most desktop displays and many laptop displays these days.