Be prepared to find issues on any tablet brand that you consider. This is not just an Apple thing, in fact you may find the lifespan of other brands to be shorter than the iPad.
I own an iPad 1 and an iPad 4 - I know the 1 can't do what the 4 can, so it has become my toddlers iPad and works great for that.
My old MacBook Pro got a little slow, so now it's relegated to my little music studio and is perfect for that.
This is life with technology from a hardware standpoint to maintain it's compatibility with more demanding software and from a business standpoint to maintain a revenue stream to continue building improved hardware. You won't be able to avoid this. Three years may seem short for a tablet to you, but if you're not demanding the most cutting edge apps, you shouldn't really be having too many problems. If you are, maybe there's something wrong with your device.