There are ties available in that configuration, but they are seldome used, sue to other problems they have, such as work-hardening of the exposed steel section, too much flex, etc.

Rail head wear is not an issue as long as a proper maintenance grinding program is adhered to.

On the issue of "pumping," this is usually the terminology applied when there is a muddy spot in the track structure due to poor subgrade, poor drainage, lack of maintenance, or all 3.
This was the big problem on the coal line in Wyoming a few years back. BNSF had not been doing ther necessary ballast cleaning/sledding/surface and lining, for whatever reason. Muddy spots developed, and combined with the coal dust blown from loaded trains, made a mixture that was like a coarse grinding compound, which steadily chewed away the bottoms of the concrete ties.

Every now and then, railroads have to relearn the fact that there is no "silver bullet" in track construction or maintenance. Just because you put in all new ties and rail does not mean you can ignore the track for decades thereafter. Drainage must be maintained, line and surface must be maintained, and muddy spots must be corrected as soon as they appear. It's a "pay me now or pay me later" proposition, with "later" always costing more.