New Zealand pushed the world's No. 1 ODI side close over the five-match series, but ultimately two batting collapses cost them. They have a chance for some fine-tuning before the Champions Trophy when they play a tri-series in Ireland during May, albeit with a weakened squad due to the IPL. Coach Mike Hesson said: "You'd love to go into a world event having all the answers but we have a couple to tick off." Is it just a couple, or are there more?

Who partners Guptill?

A number of New Zealand's quandaries are inter-related (see points 2 and 5 below) but somebody needs to walk out with Martin Guptill. Tom Latham had become a regular partner over the previous 18 months until a run of six single-figure scores (including three ducks) meant that Dean Brownlie, who had been Guptill's injury replacement, usurped him. Brownlie played some fighting innings, especially his 63 against Australia, but tailed off against South Africa. One route is to return to Latham purely as an opening batsman, but more on that to come.

What Hesson said: "There won't be a huge change for the Champions Trophy; we've won 10 out of 13 games [this season] against some good sides. We've had a couple of aberrations but the majority of our squad will be the same.

The gloves are off

A New Zealand wicketkeeper hasn't scored an ODI fifty in 42 innings. That's a long time between drinks, or bat-raising. It appears unlikely they will depart from either Latham or Luke Ronchi, but for the balance of the side they desperately need the keeper to score runs. Kane Williamson said how it's a major advantage to have the gloveman in the top five so there is the knock-on effect to the middle order and the position of Neil Broom. The faith in the two current options would appear to rule out a late change to the 26-year Tom Blundell from Wellington.

What Hesson said: "I've been delighted with the wicketkeeping of both, but no doubt both are short of runs and that's something Tom and Luke are well aware of, probably more than anyone. It's long ago that Tom was a really good performer for us at the top of the order. We know they are high quality players but have had a tough period."

Offie or leggie (or both)

Spin played a far bigger role against South Africa than was expected. Mitchell Santner was ever-present, and is the No. 1 man, but Ish Sodhi and Jeetan Patel shared the second role. Both impressed, but three specialist spinners in a 15-man squad for a tournament in England in June could be overkill. New Zealand may need to decide if they have faith in Sodhi or whether the experience of Patel - and the fact he spins the ball the other way - tips the scales in his favour. There is also Patel's wealth of English county experience to factor in. New Zealand's opening match is against Australia at Edgbaston where Patel is based with Warwickshire.

What Hesson said: "When Jeets came in against Bangladesh he did an equally good job. We are lucky that we have three very good spinners at the momen, and Todd Astle as well, who is a very good performer. It's something in New Zealand cricket that we haven't had much of, so it's a nice problem."

Pace reserves

Lockie Ferguson nipped ahead of Matt Henry in the pecking order this season and showed glimpses of what his pace can achieve, although he was expensive with an economy rate of 6.46 from his seven matches. The back-up to Tim Southee and Trent Boult in England will be important. It could yet be that Adam Milne and Mitchell McClenaghan, who were white-ball regulars before injury, are brought back into the frame although all the six names mentioned here are IPL-bound players who have permission to remain with their franchises while they are in the tournament and, thus, won't be in Ireland.

What Hesson said: "Fortunately for those guys, our main six seamers are all picked up at the IPL, so it presents a chance to look at a few young guys."

How many allrounders

If you include Ronchi, New Zealand ended the series against South Africa with allrounders occupying Nos. 5 to 8 in the order. Again, the keeping role is crucial in how this pans out going forward, but both James Neesham and Colin de Grandhomme, who has been given a finishing role at No. 8, appear to be inked in for the Champions Trophy. De Grandhomme is likelier to be able to complete his full ten overs - as he did very effectively in Wellington - although Neesham bowled better as the series progressed.

What Hesson said: "The allrounders give us balance and depth; I thought Mitch Santner was very good with the ball. Neesham and de Grandhomme grew in confidence and, quite rightly, through performances."

Andrew McGlashan is a deputy editor at ESPNcricinfo