Skipping the fact that even to clone an Android wallet from bitcoinj requires a large amount of knowledge in many different areas (c++, java, bitcoin protocol,etc) if it were 100% clone it would have been done long long ago as shown by the DigiByte wallet I've completed.
While the UI might look the same at the moment in the sneak peek that was posted there were backend changes required to adapt to the transaction comment field. When I went into this project, I like you assumed it wouldn't be overly difficult and should only take a few hours to get it functioning. Punch in the genesis block info, pubkey, packetmagic all that good stuff and bam, android wallet. That however was not the case and I wasn't willing to give up when it started to get more difficult.
The serialization in bitcoinj, for lack of a better description is complicated. Its passed back and forth between different java streams and each stream had to be updated to handle the correct serialization. The protobuf libraries from google are part of the chain and is directly what has caused the majority of the time in development. I had never worked with protbufs before and going in I had only a vague idea of what a protobuf even was.
The amount of time I spent researching and then trying to implement the new serialization would have made most sane people quit. I'm sure there are others who could have managed it quicker then me but anyone who possesses the capabilities are surely already busy with their own projects. I had to learn the bitcoin specific info as I went, a few months ago I barely even knew what a bitcoin was let alone have detailed knowledge of the protocol. HashEngineering's help was also invaluable as he helped get me back on track a few times when I was getting stuck.
When its released it will support the Transaction Comment which you will be able to set in the send coins screen, something that no other Android wallet has. I am also going to update the color scheme and will have another little surprise when its released.
This is also an ongoing project. I don't plan on dropping an apk and disappearing. Updates will be made in both UI and functionality improvements. I had always planned on getting it functioning and then working on customizing and improving. Making it function has just been more work then I originally anticipated.
Any suggestions for future improvements would be greatly appreciated!