It doesn't have to be "either/or" with the handgun vs. long gun for HD. Most people (including the OP) already own both.
You can have a pistol and light beside the bed with the pistol in a Gunvault type mini-safe. Hear bump in the night, grab handgun and light-make decision to call police. If there is an immediate threat, get ready to engage. If there is a threat, but they are still trying to get in, step 2 take a few seconds to toss on armor under the bed and grab a long gun with sling. Armor can have an empty holster for the pistol, spare mag, spare light and flex cuffs.
Though the price of armor is very reasonable now days, this concept can be accomplished with a Molle belt. Grab handgun/light 1st, then time permitting, snap on a Molle belt with an empty holster, mag, light etc. You can then grab the long gun and holster the pistol. Or the opposite, grab long gun first, then snap on the belt with pistol already in it. Limitations are really just your secure storage ability.
This concept nullifies the notion of not having time to get on the gear. You grab whatever you decide your primary HD weapon is first (and light), then you are either engaging, about to engage, or you have time to grab the rest (or most likely, by now confirmed it is a non-event and try to go back to sleep).
With 2 trained people, 1 can cover while the other puts on a vest, grabs a long gun etc. I'm working on getting my wife trained, I got her to agree to attend a 2 day defensive pistol course in the fall so that is a start. Provided I'm home, things would work best if I focused on protecting while she focused on the kids and 911 with her pistol for defense if they get through me.
As far as handguns for the OP, I'd get a G21 since you already are familiar with the G26. .45 ACP, rail and will be under the $650 no problem.