Looks fantastic!
You can remove the spring and copper washer from the agitator shaft and discard. Those are internal parts from the 0A4298 shaft seal you removed.
A little hard to tell with the spring in the way, but the agitator shaft looks like it's in great shape. I always recommend a stem and boot seal replacement right off the bat to prevent water contamination from destroying the agitator shaft, upper sleeve bearings, and contaminating the transmission oil.
Couple of things I recommend:
Get a 205000 kit for the motor carriage. Whirlpool discontinued these last year so whatever is floating around out there is IT. Here's a the cheapest one from Ebay
https://www.ebay.com/itm/4038298377...Avb1ypFQdl4UDg8RKoldymOSA=|tkp:Bk9SR8KE1tbVYA
Take some time to properly adjust the pump belt. Most put too much tension like a automotive drive belt and it causes the transmission belt to run loose and not fully tension correctly. If you want to make an error, adjust the belt on the loose side. Replacing either the drive belt or pump belt affects that adjustment (No 2 belts are exactly the same dimensions).
If you have some turbine oil on hand, you can remove the screw (old style) or bolt (new style) from the center of the water pump body and shoot some in there to lubricate the bearings. Otherwise, I think you have all the bases covered.
