That jamis explorer a2 looks like a fine bike.
When bike manufactures install suspension forks and seat posts on entry level bikes, Like a Giant Sedona DX, They may be optimised for "average" riders, perhaps in the 150 - 225 lb range. I know they often have an adjustable preload feature but not sure how effective it might be for men over 200 lbs. I would ask the dealer if a suspension fork would be suitable for your needs. If it is, Look at the Giant Sedona DX. If not, The base Sedona might be a fine choice too after swapping out the suspension seat post with a rigid one, or a custom suspension post for your weight.
My Sedona only has a suspension seat post, Which seems to work well for recreational cyclists absorbing big bumps and isolating me from smaller vibrations, But even at 145 lbs I have the preload set up pretty high, I don't know how well it would work for a heavy man. I'm guessing most suspension forks might have the same limitations. Some better hybrid bikes offer air charged suspension forks that might be adjusted to accommodate your weight.
My next bike will have suspension forks too because I often encounter some rough patches on roads, Sidewalks and MUP's I ride on. I don't know what effect properly adjusted suspension components has on peddling efficiency on smooth roads, They probably do reduce it some, But for recreational cyclists or commuters who regularly ride on rough surfaces it might be well worth it.