Sprint has lost a lot of coverage over the past few weeks..if you look at your coverage map...you will notice that it completely changed..sprint before had towers which were not theirs but they were using as theirs..they renegotiated the contract and now most of it is 3G roaming..
You can try to load a different Radio or PRL and see if that helps...but if you got hit by the roaming change then thats a different story..
So far I have found speeds/connection to be on par with my TP2 in my area..and I use both at the same time...
As for your keyboard issue..its a known issue and its a software issue, not a hardware issue..we have a fix..just load up a custom kernel with a keyboard fix...
Edit: To your edit, we also have fixes for the battery issue too..visit our Epic section: (Though your drain may be linked to poor signals)
http://forum.ppcgeeks.com/sprint-epic-4g/
Also, personally I don't even charge my phone anymore..I bought 2 spare batteries + external charger for 7$ on ebay...so whenever I run out of juice I just put in a new battery (phone reboots in 15-30 seconds). And put in new one..then when I am home put the used up battery on external charger...