I too have a front wheel drive 1st Gen HRV and do all my own vehicle maintenance.
You could drill a large hole in the lower engine cover for oil filter access but you would still have to drill another large hole for oil drain plug access.
At that point the already chintzy panel would have no strength and you would throw it away.
Plus you still will need CVT trans fluid access eventually.
Removing and re-installing the under engine cover is another step but no big deal.
I do recommend to start collection of a variety of plastic push pin clips for the lower cover and various other covers for the HRV.
That way when you break or lose one of the clips, you have spares on hand ready to go...
Keep some kind of log for all your vehicle maintenance and you will be fine at resale or trade-in time.