Regarding your last point: A depreciation of the currency is generally positive for a country. Expensive imports give incentive to use local products (e.g. food), at the same time exports become more competitive. That is the reason why the US accused China of keeping it's currency weak for years. It's the volatility in the exchange rate which makes it harder for companies to plan reliably, but most will profit from the new level (except airlines).
So while there will be some inflation (estimated at 3% at the moment), the economy profits from the exchange rate movements. The underlying problem is that the GBP lost value because of the uncertainty, and this uncertainty is not good for the economy. However, people voted for Brexit and a lot of them are happy with the result. So this uncertainty won't necessarily lead to less consumption. Current economic data looks better than what was anticipated before.
So as long as people are happy with the current situation and the outlook, the economy could actually profit from the vote in the short term. The longer term is of course very dependent on the deal that the UK will get.
Regarding your other points: A lot of promises were made in the campaign that are completely unrealistic (£200mln a week for the NHS). Not being part of the government makes it easier to ignore those promises. Boris is probably one of the only ones who could face questions at some point, in case the deal isn't as great as he believes.
As Conservatives are already in favour of a hard Brexit, it's hard for UKIP to get many voters in that space and to gain more seats in the next election. Farage saw the chance to sell the vote as his win (although he wasn't even part of the official campaign) without having to implement any of the consequences. The party is an absolute mess. They don't seem to have a lot of competent people, so Farage basically had to take over again. I don't think he planned that. Especially as they'll have to find a motto now. Their purpose was to get the UK out of the EU. With that done, the question is why people should vote for them.