Seems you're not looking to quit work any time soon, so I'll ignore that part.
So long as the mortgage does not bother you to keep, I'd hang onto it. You're probably paying (after tax deductions) in the low 2.xx% range effectively on the mortgage, whereas almost any reasonable investment will likely outperform that over an economic cycle (even 10 yr treasuries would be close to that).
I'd keep your allocation and go forward with it. I think the 10% in p2p, and assuming you have 5-15% in bonds, you've probably got at least 75% equities... ignoring the value of your primary home... is perfectly fine for your position. You could very well hit 2mm within 5 years.
At this point, if anything, I'd be looking for ways to increase passive income, rather than just focusing on net worth.
A conservative calculation tells me you've got roughly 25k in passive income annually (465 * 3.25% and 120 * .08) on the low end. That's fantastic! A mixture of investing new money into p2p, bonds, dividend paying stocks, etc, could yield solid increases in passive investment income for the next few years. Depending on your abilities/preferences you could also venture into rental property. If you are so inclined, you are also on the brink of being able to get into "sophisticated" investments in private funds and the sort, however, that sort of defeats the purpose of being "hands off" and letting your money work for you. If you've already won the game, why keep playing?
In any case, I'd take some time to reflect on your risk appetite, 5 yr goals (income/net worth/personal goals/etc), and see how you can adjust to move in that direction. Financially, there's a lot of flexibility to be had right now, so congrats!
Good luck on whichever direction you choose.