Yeah the FPU portion of the code goes up in very rare cases to 30%, in most cases it is lower, maybe 5%. So the average speed gain due to faster FPU of the P60 has no major impact.
About Pentium I boards:
It really depends what you are up to. If you want to have 3D accelerated graphics you go better with a P3 or Athlon system.
I also got two Pentium I systems running.
I chose a P166MMX on a HX board. It's not about speed but overall comfort.
P166MMX does not show the TP speed bug already and also DoTT sound does not bug. On the other hand it has MMX, a good PCI performance for graphics intense DOS games. The board has 4 ISA and 4 PCI slots, IDE, fast serial already onboard. Though IDE caps with Busmaster DMA at 15 MB/s, if you need more plug a UDMA controller like the Highpoint 372N.
On the other hand you have 6 memory slots and can upgrade upto 512 MB or at least beyond 128 MB. So a windows for data transfer (network, amiga, atari, c64 etc.) runs very well, even with USB mass storage devices.
It's good for all the demanding DOS games and can even run NT4 as 32 Bit OS for some of the more modern application. It can also be used for low end 3D accelerated games using Riva128 or Voodoo1.
You can plug all of the common ISA soundcards and got a rock solid stable system.
You can't do more demanding 3D games. But then again these run at most even on a current PC platform under Win XP f.e.
Ofcourse you can take the step from a 486DX4-100 with local bus to a P3 system. Though I think a pentium board is a more versatile platform in this performance range.