I believe that this world will be much better in the future, but there will always be pain and suffering and physical death on earth since that is the nature of this physical world.
I don't understand why anyone would want to live forever on earth. According to my beliefs there are much better worlds waiting for us after we die.
“As to thy question concerning the worlds of God. Know thou of a truth that the worlds of God are countless in their number, and infinite in their range. None can reckon or comprehend them except God, the All-Knowing, the All-Wise.”
Gleanings, pp. 151-152
“O My servants! Sorrow not if, in these days and on this earthly plane, things contrary to your wishes have been ordained and manifested by God, for days of blissful joy, of heavenly delight, are assuredly in store for you. Worlds, holy and spiritually glorious, will be unveiled to your eyes. You are destined by Him, in this world and hereafter, to partake of their benefits, to share in their joys, and to obtain a portion of their sustaining grace. To each and every one of them you will, no doubt, attain.”
Gleanings, p. 329