It is likely that you will take the new items with you and so it wont be a wasted spend and could end up selling your home if it helps to make the room appeal to buyers. If you dont take them with you and the buyers like the space, you could offer to sell them - this is particularly handy for first-time buyers.
While its important not to go over the top, a well-presented dining room will always have an injection of colour. It doesnt have to be bright yellow. It could be a subtle light green with matching curtains that have a pop of pink in them.
To visualize how a bigger piece of furniture will look, take the time to block out the length and width on the floor, and also the height of the table. I usually stand on my tape corners with a tape measure, then try to fill in that space with furniture of a similar size, and take a step back to see how it’ll feel. It also helps to have a friend stand there with the tape measure while you have a look.
The only real consideration in buying this style of table is whether to go for an upmarket one, such as a French colonial table, or one with the rustic appeal of an English country farmhouse.