Since you want a bigger loader and heavier front end..... they both fit your needs... I know they both use the same "bigger" loader (823) and I believe they both use the same front axle.
Therefore, I would keep my $2k and buy fuel, filters, tools, implements, or anything else.... Plus, I positive the 4330 can do anything the 4630 can do!
For what it is worth, I am going to be putting my money where my mouth is and buying an
L4330...
Lastly, I don't know what loader you had on the 3830, but if you were truely disappointed in it, you might want to consder going larger than the Grand L tractors!
Ask yourself what you need the tractor for and what you want the tractor for... You should be able to get by with what you NEED... But, if you have extra money, there is an entertainment value to the smaller tractors. Which, I consider anything under 100hp to be a smaller tractor.