Re: Eriksen, I really like him, but I think Mourinho was basically right to get rid of Mata in that a 10 in a 4-2-3-1 really needs to be incredibly productive to justify being mediocre defensively in such a key position. If Soldado, Lamela and Townsend/Lennon all produce fine seasons due to Eriksen's playmaking, than fair enough. But that's the focal point position. Same reason why Rooney can score 15 goals playing as a 10 and still not have had an incredible season in that position. A 10/SS can have a great season without really moving the needle a ton. Look at the the players in the hole in the Prem: Ozil, Mata, Oscar/Cesc, Eriksen, Aguero/Toure, Barkley, Sterling/Coutinho. If 2 of the young Merseyside players have the season they're capable of, I'm not sure any of those players will be a ton better than 4 or 5 of their rivals. More likely, Eriksen will have a fine season and Spurs will get the 4th or 5th most production in that list, right?
The case for Oscar is that he's a plus defensive player at his position in addition to his good work offensively, unlike everyone else on that list.
Re: Soldado, He's not a bad overall player, but his strength is movement and finishing. Spaniards look like all-around talents in the Prem, but I would expect more goals from him and comparatively, his other work will be seen as less impressive. I don't think he's the creator for others that Giroud or Rooney are, for example.
Re: Transfers, I totally agree. A partner for Vertonghen and a left-winger and they'll have a serious chance at a top 4 situation.
I think you've found a really, really promising manager, but Arsenal, United and Chelsea have all strengthened significantly, and you're miles from catching Citeh, and with your 4 wide starters right now being: Lamela, Lennon/Townsend, Davies and Walker, that's not going to change.