If you are a very dedicated user, you may accept that your internet is slow as heck for 50% of the time.  Most won't, and will opt for lower security and less privacy with an SPV wallet instead.  I don't think spam is important enough that we should accept more centralization or forcing lower security upon a lot of users.  As the malicious attacks has demonstrated, there is plenty of room for all the non-spam transactions in 1MB blocks.  If your goal is more spam and lower security and privacy, the answer is larger blocks.  If your goal is to make transactions confirm faster, the answer is better spam filtering.

There is another option, if you insist on a hard fork: Smaller transactions.  Using different crypto algorithms, the size of each transaction can be reduced to about 1/4th of the current size.  This unfortunately come with the cost of higher CPU consumption.  Nothing is free.  With each transaction taking 1/4th of the current size, we can do with a block size of 250k for years to come, allowing even users with metered internet and mobile connections to run full nodes.  Assuming spam filtering, of course.  If you want to abolish spam filtering entirely, then no block size would be large enough, and no personal user will even dream of doing a full blockchain download.