It looks fine to me.
Your thanks to your uncle should be general, not specific - can cause rifts for all sorts of reasons.
As advised, speak up - it will feel loud to you, but not to the audience. Ignore any hecklers, don;t get into a one-upmanship routine with the 'wit' of the party, there is always one.
If you are unsure, write your speech out word for word in print large enough to read easily without squinting. break it up into sections.
T
ake your time, and speak slowly, and take some deep breaths in each break.
It will go fine, have a wonderful day - and life together.