If it is becoming unbearably slow... then I'd recommend:
1. Exporting the private keys for the 2 addresses you want to keep from your current wallet (NOTE: make sure you keep the seed for this wallet as well!)
2. Create a new wallet generated by importing those 2 private keys (New/restore -> Import Bitcoin addresses or private keys)
3. Create a new wallet with a new seed (New/restore -> Standard wallet -> Create a new seed)
4. Send everything from old wallet to new seed-based wallet created in step 3.
Then you can keep receiving the transactions on your "old" pool addresses, but have a 'smaller' wallet (just the 2 keys) that won't be slow to load/use etc... maybe consider consolidating any coins from this into your new "seed-based" wallet occasionally.
And you can use the new seed-based wallet for your "everyday" usage.