The potential problems with removal of runner are dependent upon how the runner was installed. Some dearies actually tack the runner to the steps, tread and riser. Ouch, because removal leaves those holes to be filled and stained to match (very difficult to conceal). An alternative method is to use carpet bars which come in wood or metal, in an assortment of finishes. This is slightly more expensive but imo, also *looks* more luxurious. The carpet is barred at the back of the tread where it meets the riser; best practice has the runner tacked beneath each tread rather than slanted from top-front to the back of the next lower riser. Note that under-tread tacking also uses the most running feet of carpet, so the most finished appearance is going to cost. There are several other methods, so discuss intent with the installer before s/he does the work. One thing for sure, is to not use any sort of sticky-back tape: it either doesn't hold well, or holds too well and removel is labor-intensive. Because of the carpet pile height, if possible choose treads that are slightly deeper than usual so as to maintain fully safe depth.

He's just as likely to fall from too much traction on carpet as he is to slip on a hardwood step. Bare feet have pretty good traction. You can get clear "traction tape" online. I've seen crawlers on staircases and they KNOW what they can handle. Many of them adopt the sit and bump on the butt mode of descending, or turn around and come down in a foot-first crawl. They are much better going up than down for quite a while, but by the time he's 2 he'll be going up and down with no problems.

If you've ever fallen on stairs, both carpeted and not - you would want carpet on them. I hate carpet and have wood everywhere but carpet on the stairs. When I was building my house I did a lot of research and discovered the bulk of it recommends carpeted stairs for safety. I considered wooden stairs with a runner, but I've had that before and found all the nooks and crannies were horrible to clean. And I've had a 1920's era wooded staircase (two sets actually - one for the family and guests and the second hidden one for servants that sadly didn't come with the house when we purchased it) - had to add these rubber stair treads on them so they weren't so slippery for my older relatives which sort of ruined the beauty of the wood. rubber non-slip stair treads

We have gotten estimates for refinishing and carpet - assuming that the existing treads are salvageable, refinishing wasn't that much costlier overall (depending on the price per sq ft of the chosen carpet, of course). However, that didn't take into account the glued-on plywood or the likelihood that the original treads are toast. Refinisher charges $250 per tread to replace, which blows the budget entirely. I have also seen some photos of staircases with just one full wood tread on the bottom step, with the remainder carpeted. It's a bit odd, but if done right it kind of emulates the look of a runner. I was also thinking that I could remove the plywood just from the rounded end of the bottom stair and refinish the wood, so that bit isn't wrapped in carpet, and then run the carpet straight down from the preceding stair. The carpet would sit up higher than the stair, but I could cover the bare plywood edge with some molding or something.