re: L1
SOHO should indeed have a successor and also located at L1 (Earth-Sun); studying the Sun in a continuous basis through different wavelengths and with a coronograph. This pure science and practical safery concerns;
And on the other side, a camera pointed towards the Earth for educational purposes (with a stargraph to show the star background crossed by our planet; one degree every day and costing a fraction of the Sun oriented experiments).
L1 is a very interesting place for observations and should be visited more often.