I intend constructing a hall in which Islamic functions such as walimahs, could be conducted strictly according to the Shariah.

Answer

For a Masnoon Walimah there is no incumbency to invite every member of the tribe/family. The obligation of the Walimah rests on the groom. He should invite a couple - a handful of people to his home for a simple meal. There is absolutely no need to invite the entire tribe. Sahaabah would also marry. They fulfilled the Walimah obligation without inviting even Rasulullah (Sallallahu alayhi wasallam). In fact, many or most married without even informing our Nabi (Sallallahu alayhi wasallam) of their proposed marriage.

Your idea of constructing a hall for walimah and similar functions is in fact a trick of the nafs. You will be moving into the wrong direction with such a wasteful, anti -Sunnah project. Those who marry should have simple walimahs at their homes in the style of Rasulullah (Sallallahu alayhi wasallam) and the Sahaabah. The arguments you have proffered for the project have no Shar'i validity. Rasulullah (Sallallahu alayhi wasallam) said:

"The Nikah with the most barkat is the one in which the least expense is incurred."

Before embarking on any venture, first understand the requirements of the Sunnah. The Shariah is the Criterion. If anything conflicts with the Shariah, it is shaitaaniyat regardless how plausible and rational the logic may appear.

Todays wedding feasts are NOT Walimahs. They are functions of riya and takabbur which are bedeviled

with la'nat

food of a debtor. A debtor is not allowed to invite people for meals. His first obligation is to pay his debts. His attitude is absolutely reprehensible. Rasulullah (Sallallahu alayhi wasallam) had refused performing even the Janaazah Salaat of those who died leaving debt.